I liked X-MEN: EVOLUTION quite a bit, and it was easily the best Marvel cartoon of the 21st century so far (although, admittedly, the only Marvel shows that aired after 2000 so far were SPIDER-MAN UNLIMITED, which'd been left over from '99, and "MTV" SPIDER-MAN, which had great visuals and action, but the plots were repetitive). Unlike the 90's X-MEN, it had great animation quality and chose to focus on character development over action sequences (of course, network restrictions always hampered action on kiddie shows). While the fact that the majority of the cast were teenagers (Wolverine & Storm being a compromise, which is fine as both wouldn't have worked well as teens) was due to Kid's WB's insistance, as well as omitting much development on any adult character over 18 (even Wolverine!), it captured and reimagined the spirit of many classic characters, especially Cyclops, Rogue, Kitty Pryde (who'd NEVER been in a series before, save for PRYDE OF THE X-MEN pilot and a guest shot on SPIDER-FRIENDS), and others. The first season was hit-or-miss and the second season suffered from "overcramming" of characters, it hit its stride by the second half of the sophmore season, and from there it hit the ground running. Season 3, now out as a box set, is argueably the pinnacle season of Evolution; the storyline is tense and none of the episodes feel wasted. Season 4 only had 9 episodes and unfortunately some of them feel "wasted" as they either introduce characters who never appear again (Like Legion) or flesh out ones that we barely care about, like X-23, over, say, Colossus (who usually gets shafted in cartoons). Still, the series finale to the show, "Ascension", was agrueably one of the most satisfying endings to a Marvel show (aside for the 90's X-MEN and IRON MAN, of course) and was basically a testiment to what the show could have accomplished.
Sadly for everyone on board, inter-company and management issues have marred the distribution of this series, despite the fact that it had solid ratings and is still fairly popular, some 2-3 years after it ended. Kids WB is connected to WB, which is connected to DC; they're not as chummy with Marvel anymore and so they know that amping up Evo would simply add dollars in Marvel's bank indirectly, so they seem to be only interested in Evo if there is an X-movie release in the horizon (the final 12 episodes of the show were put on haitus for some 8 months before airing to basically "coincide" with X2, which they didn't do because X2 was no longer in theatres by the time the series finished its run). Secondly, Marvel was apparently not satisfied with the "compromises" they had to make to get the show running, so they chose not to bother with any more episodes after 52 were up, and WB has had no interest in reruns. In fact, the final 12 episodes have NEVER been reaired on U.S. TV (Evolution reruns in other countries, like Canada, the U.K., maybe Australia, etc). As such, the DVD releases have not been great; bleeding out the series with 3-5 episodes a disc and then waiting a full year before releasing Season 3 (before that box set, the last Evolution DVD release, finishing Season 2, shipped in November, 2004). Its a shame that Evolution seems to be getting burried due to management issues (the same issues that keep many 90's Marvel shows from decent releases), because this show deserved better.