Had a couple extra hours last week, and I saw it. I saw the original when it first came out, and have nothing more than vague recollections of it at this point, but I remember liking it. I'm not really an anime fan, but my understanding is that the attraction is that they are typically more "deep" and adult than a "normal" cartoon, and the original was "deeper" than most anime.
Well, the sequel totally went off the deep end in this regard. Action, fun, etc. all took back seat to the philosophical sort of ideas the movie was trying to get across. There was very little action, and I really had no idea what was going on most of the time - and no, not because of the subtitles (I can read, thanks). A good 5% of the dialogue was probably quoting various philosophers.
As far as the animation (I'm no connoisseur), the characters, cars, etc. were animated on top of a rendered CG background - the difference was obvious, and just didn't look right to me. I'd guess that anime purists would really like this either.
Rocko