Hoo boy... where to start. How about the primary issue... Why is this necessary? We already had an excellent 2D version of The Clone Wars created by Genndy Tartakovsky that was highly stylized and very well done. This one is fancier, with 3D CGI and a more expansive story that will be told (the film is an introduction to an animated series that will run on Cartoon Network as well this Fall), but what is the point? We already know how the story will end!
So why was that not an issue with the previous version of The Clone Wars? Because it was broadcast in between Episodes 2 & 3 of the live action movies. We didn't know how it would turn out, and it was a bonud story to help fill in what happened during the gap. But now, the entire story has been told, we know the conclusion, and I don't really see the point.
Beyond that you'll be annoyed within seconds of the film starting as Lucas has done away with the traditional "crawl" which brings you up to speed as it fades away into space. What did he replace it with? A voiceover that sounds like it was recorded by some cheesy game show host, describing events that led up to the start of the movie. I kid you not.
Anakin, Ashoka and Obi-Wan in a scene from The Clone Wars
What else? How about an uber-annoying "tween" female Padawan that is placed under Anakin's care? This character doesn't act like a Jedi in training, she acts like a typical Junior High student that's used to being spoiled by her parents. VERY annoying (she actually even annoyed the heck out of my own 12 year old daughter). I also found her kind of creepy as compared to the older characters she looked like she was 10, but had C-cup breasts that were housed in a tube top. Very appropriate for battle.
Lots of snarky repartee ensues between her and Anakin and it's like fingernails on a chalkboard.
Then we have Jabba the Hut's brother (I guess). I'm a bit uncertain because he sounded like either Truman Capote or just plain female (another item that confused and annoyed my daughter). Also making an appearance was Padme in a seemingly spray-painted on costume. It wouldn't bug me so much if this was anime targeted at a slightly older crowd but the target is really little kids. The audience was chock full of cute little ones running around with light sabers and Darth Vader helmets.
I'll admit that by the time I was about 2/3 into the film, I actually started to enjoy the ride a little bit (and that's why I rated it as high as I did), but overall I think fans are going to be disappointed.
Overall it was like watching a fireworks display: A lot of sound and fury, but not much substance.