I should start this out by admitting that I've never watched the original Transformers show. I've seen (and loved) all of Beast Wars, and seen (and not really liked) bits of Transformers: Cybertron and Animated. Never seen any of the movies, either. So... yeah, I've gotten that out there. I'm almost positive there are diehard fans who strongly disagree with me on this subject.
So, now that I've admitted to my semi-newbie status, let me say this: if you like sci-fi and are willing to accept giant talking, transforming robots, watch Transformers: Prime, because it is incredible. cardboardwalk from BehindTheVoiceActors.com described it really well: "With the cinematics of Bay, the mythology of the original, and the story telling of [B]east [W]ars, this show is awesome!" Really, for anyone familiar with these three adaptations, that its the nail right on the head. Even if you don't understand the comparison, give it a shot--like I said, I'd only actually seen one of those three when I started watching!
First of all, I want to add something cardboardwalk left out: the voice cast on this show is phenomenal. Obviously, Peter Cullen is an amazing Optimus Prime; the regal voice fits his great performance, assuring that even some of the (occasionally) corny dialogue doesn't bug you, not coming from him. And saying that Frank Welker plays Megatron amazingly almost goes without saying, since, well, it's the original Megatron, and it's just Frank Welker.
This is just the part that should satisfy the diehard Transformers fans--if you're a fan of voice actors in general, there's plenty to pick from! ;) There's Steve Blum as Starscream (I'm of the opinion that he can take any line of dialogue and make it awesome), Josh Keaton, Kevin Michael Richardson, Jeffery Combs, Daran Norris, Adam Baldwin and Gina Torres (both playing rather different roles than in Firefly ;))--these are the ones off the top of my head! And that's also just the names I recognized before I started watching. Sumalee Montano, for example, is a voice I hadn't heard before--but she's another example of the amazing casting decisions here.
The second thing I have to talk about is the animation. I know that CGI, in general, is a turn-off for a lot of people, so let me say this: barring the human models (which are sometimes a little disproportionate), the animation is absolutely beautiful--my brother and I watch the show together, and sometimes we forget that it's a TV show, not a movie. It's not just the models or transformations, etc.--it's how the show moves. The action is choreographed to not only give a greater intensity to the fights, but also keeping in mind that these are giant robots and trained warriors. (There's even a scene in the five-part series premiere that shows the fighting from the perspective of the human kids.) We've had plenty of "Wait, back up, I want to see that again" moments while watching this show!
But, relatively speaking, these are both pretty superficial things to talk about. So, here's the question: does the substance of the show hold up as well as its appearance?
The answer is--absolutely. The writing on this show is incredible, well-planned and character-driven. All the main characters, and even some of the villains are given time to shine with their own episodes or arcs. First season, admittedly, had quite a bit of filler--but that's mostly a warning for the people who don't like filler, because I like it (when it's done well). Also, all of the "filler" generally had some overall purpose, like character development or establishing a plot element. One thing that I think serves this show well is that there isn't, per se, a single overarching plot that they always tie into, aside from the premise of the show (which is, basically, the Autobots defending Earth, against the Decepticons--and other threats). Instead, it's a variety of potential plot developments, which intertwine or act alone as best fits the story. It gives them plenty of chances to go back to all of the villains and ideas they've left open on previous occasions!
Also, the characters are very well-done--for the most part. All of the Autobots have things about them that I like. The one that stands out the most, unsurprisingly, is Optimus Prime. I'm used to shows where the "leader" is either completely bland, or your stereotypical teenage hero--meaning rash, inexperienced, and generally not really fit to lead (the plot finds some way to keep him in charge). Not Optimus. He comes off as the writers intend: a wise leader, always putting his people above himself, and protective of this new planet he has adopted (so protective he's not willing to have human casualties, even from humans who attack him). The leaders of the Decepticons aren't far behind, either. Megatron is a calculating, menacing figure, whose only real failing (as a villain) is that he lets certain people live for too long. While he's not the "come up with a master plan that takes all season to unfold" type of villain, he's both good at making plans, and thinking on his feet (just look at the season 2 premiere--actually, don't, not until you've watched first season). To top it all off, sometimes, you can almost feel for him. He's not evil for evil's sake, he just leads a group who are darker and more ruthless than the Autobots--and occasionally, it does seem like he almost misses having Optimus as a comrade. And, of course, there's Starscream. Given how many people he has killed or tried to kill, and how many messes he gets himself into, you really shouldn't feel bad for the guy--but you still do. Then again, you never really know when he's truly helpless--or he's feigning it, and he's actually playing you like a violin. (Incidentally, it can be both at the same time.)
I can't talk about the characters without mentioning the show's one major failing. Her name is Miko. Okay, so the human characters aren't all that interesting compared to the Autobots, for the most part. I should clarify, the three main characters all made more interesting (or tolerable) through their relationship with one of the Autobots, though Jack (the oldest/most mature human) and Arcee's clearly take the cake here. The primary problem with that statement, though, is that Miko's relationship with "her" Autobot, Bulkhead, brings out the best in him--and the worst in her. Describing how much I dislike Miko should probably be reserved for a more in-depth look at the show, but suffice it to say she's insanely selfish, to the point where she's just obnoxious. (And she all-but manipulates Bulkhead to her own ends, and when he needs support? She drops him like a hot potato.) Basically, if you watch this show--do your best to ignore her and focus more on other characters. She does get much better in Season 2--primarily because she has such little screentime.
I'm sure there's more I can say, but for now, I'm going to conclude with the number one thing that makes this show kind of unique--and enjoyable!--for me and my brother. The show spends its time developing the fact that this is a war between various factions, some more heroic than the others, mostly concerning these giant aliens. That actually makes it sound terrible, but hear me out. For one thing, the writers are good about remembering that the Autobots and Decepticons are aliens and ancient--they have long, long histories with each other, etc. They also, Autobots and Decepticons alike, miss their homeworld, their own culture, and fighting on a more open battlefield. This is especially well-developed for Optimus and Megatron, partly because some of this comes off of how they play off each other.
But I'm also referring to the lack of magical MacGuffins*, "ultimate transformations", etc. in the show. Yes, there are artifacts of great power**, a valuable resource (Energon) that both sides need to get their hands on, stuff like that. There's even some amount of a sort of mysticism (though I wouldn't put it in terms of outright magic). But, that's now the writers resolve problems or drive the plot. The plot is driven through tactical decisions, (relatively) down-to-earth and beautifully choreographed battles (no "STARE AT THE EPIC DEUS EX MACHINA" moments here). Again, it feels like a war between factions--not a backdrop invented to give the characters some reason for being here and fighting something every episode. This also contributes to the show's ability to pick up and develop plot threads when needed. The show isn't an overarching mystery that the characters need to solve, or even one specific goal; situations change, plans fall apart, all parties have to react. And that just makes it a treat to watch.
*Yeah, so I read TV Tropes--a lot. Fair warning if you follow any links--TV Tropes can be very addicting, and isn't always G-rated.
**NOTE: Since writing this post in the first place, I've seen more of season 2. They've started involving more of the "mystical objects", but my problem with mystical artifacts is when their power is either undefined, or so ridiculously over-the-top that basically, the series has to come to a standstill as a result. These tend to be treated like powerful weapons, whose effects are defined, and their threat level is both determined by those effects and the intelligence of their user. They are not powerful just because.
So, I've basically rambled on for forever about all this. Long story short: if you're looking for smart writing, beautiful animation, and a great cast of characters, try out Transformers: Prime. Again, I can't really tell you if a die-hard Transformers fan will like this show, but I was a casual-at-best fan who loved it. I recommending starting with the pilot 5-parter, since that (for once!) is a fair indicator of the show's overall quality (aside from some slightly disjointed animation, which improves as the season goes on). Peter Cullen's voice alone will probably hypnotize you into watching the rest of the show. ;)