Maybe that's what helped me enjoy it so much.
All in all, X3 is surprisingly good. It has two main plot threads, both of which are taken from strong arcs in X-Men comics. From "Gifted", Joss Whedon's first arc of Astonishing X-Men, there's the idea of a mutant "cure", one which has mutants lined up around the country to rid themselves of their "affliction." From the much earlier Claremont & Byrne run on Uncanny X-Men comes Dark Phoenix, in which Jean Grey's power is magnified immeasurably just as she spins out of control. Of course, both of these concepts get modified for the movie -- Dark Phoenix is now a repressed side of Jean's personality rather than the result of various cosmic interferences, and the alien presences are similarly removed from the cure story. These changes are for the better, retaining the strength of the ideas while jettisoning all the complicated continuity stuff.
Not that the movies don't have continuity baggage of their own to take care of at this point. As we pick up from the end of X2, Nightcrawler is gone without explanation, Pyro is now a confirmed member of Magneto's team, and Mystique has been captured. There's apparently a new president, but he is mutant-friendly, or at least mutant-tolerant. Hank McCoy, last seen in a tiny cameo on a bar TV, has transformed into his blue and furry incarnation, and is now played by Kelsey Grammer. Grammer isn't a bad choice to play the character, but it's mostly a distraction to hear that Sideshow Bob/Frasier Crane voice coming from underneath all that makeup. The movie wouldn't have really lost anything by using an unknown in that part.
Speaking of new characters, X3 also introduces Juggernaut, Multiple Man, Leech and Angel, and considerably beefs up the presence of Colossus and Kitty Pryde. We also get a fun glimpse at Sentinels and the Days Of Future Past timeline via a Danger Room session. For that matter, it was awesome to see the Danger Room make it into the movies at last, though its sole purpose seemed to be to set up a few jokes. There are not one but two Fastball Specials. There are also some pseudo-Morlocks, and a very pseudo Callisto, who bears virtually no resemblance to her comic self. There are tons of nods and sly winks to the comics lore everywhere, so much so that I really have no idea how someone unfamiliar with the comics would respond to this movie. Ratner isn't nearly as deft a storyteller as Singer, and may be relying more on geek-knowledge to fill in the gaps. I can't quite step far enough outside that geek-knowledge to tell.
In any case, there is a lot of mutant stuff jammed in here, and it mostly comes at the expense of character development. There's a limp gesture at a romantic triangle between Rogue, Iceman, and Kitty, but it never really goes much of anywhere, and serves mostly as a motivator to get Rogue depowered. The Dark Phoenix story exists to provide a worthy adversary for the X-Men, not to help us learn anything new about Jean. Wolverine's story is pretty much resolved at the end of X2, Xavier and Magneto are doing the same old dance, and Storm, well... more about that in a moment. Creating significant character development in a superhero movie is always a highwire act, and even more so in a team superhero movie. This is another area where Ratner doesn't really measure up to his predecessor. Singer was a master at conveying layered emotion quickly (think of Pyro gazing at Iceman's family portrait in X2), but Ratner's interest lies in getting to the next action setpiece. Political and social developments are pretty absent as well. X2 worked the gay metaphor effectively, but it's buried deep in the subtext here. The cure storyline in particular lends itself to symbolic parallels, but the development of these parallels is more or less left as an exercise for the viewer. For some reason, I didn't mind this as much as I might have. Yes, some deeper emotional notes would have made X3 a much better movie, but I still had a great time -- maybe it was that comic lore filling in the gaps again.
The weakest part of the film, as with the other two X-Men movies, was Storm. I love Claremont's Storm as a character, and by rights she should have had a strong presence in this movie, her wisdom and otherworldly demeanor counterpointing Wolverine's gruff impulsiveness. However, the Storm of the X-Men movies drains everything interesting from the comicbook incarnation. She is not African (Berry's halfhearted attempt at an accent in the first movie notwithstanding.) She has never displayed any particular connection to the earth, aside from controlling the weather, and she certainly has never been a life-positive pacifist. She's pretty much just a hollow action-hero cliche, tossing off special effects and tough-guy lines (though none this time as painfully lame as the first movie's "Do you know what happens to a Toad when it's struck by lightning?") She should be the one admonishing Wolverine to use non-lethal force, but instead she's gleefully electrocuting Callisto against a wire fence. I have no idea whether these choices stem from Berry, the directors, the writers, or some combination, but they serve to make all the movies less interesting than they could be. The fault is most glaring in X3 because she has the biggest role in this one.
There were some other weak parts as well. The actor playing the President, Josef Sommer, is given some very inane lines to say ("Then God help us all!") and can't quite manage to sell them. The entire Phoenix storyline takes place without one single manifestation of the Phoenix effect (you know, the big fiery bird thing), which was disappointing to me. In fact, all the fire-imagery set up in X2 is pretty much missing from Jean in X3. The effects are all just as satisfying as usual, but I think a huge phoenix over Jean at a climactic moment would have been spectacular, and I can't really understand why the movie omitted it. Financial reasons, maybe, and if so more's the pity that they couldn't save the money on Grammer.
The film certainly does have its moments, though. In particular, there's a fantastic moment at the beginning, with an adolescent Angel trying desperately to cut off his budding wings and tearfully apologizing to his father, who says upon discovering the mess of blood and feathers, "Oh, Warren. Not you." This moment is not only one of my favorites of the whole X-Men series, but of all superhero movies I've seen. The notion of having Worthington Enterprises be the ones behind the cure is brilliant, and even though Angel remained more or less a symbol rather than a person, I still loved how the movie handled him. Ian McKellen and Patrick Stewart were just as satisfying as ever -- McKellen was particularly great as a villain whose point of view makes perfect sense. His instant desertion of Mystique once she was no longer a mutant was a chilling reminder of the heartlessness at the core of his philosophy. Famke Janssen had a terrifically blank look as Dark Phoenix, and Hugh Jackman delivered the goods as usual. Aside from Berry, the casting has always been excellent on these X-Men movies, and the new additions carry on the tradition nicely, particularly Eric Dane's knowing smirk as Multiple Man.
I have to say, I was rather shocked at all the killings and depowerings in this movie. At the end of the film, the core cast is pretty much decimated -- Magneto, Rogue, and Mystique depowered; Xavier, Cyclops, and Jean Grey dead. Of course, Jean was dead at the end of the last movie too, and anybody who knows superheroes knows that death is often just a minor setback for them. Still, after a while one couldn't help but think of expiring actor contracts. I feel relatively sure that even if there are more X-Men movies (and I hope there will be -- I imagine Marvel does too), at least some of these people won't be coming back. This movie isn't a perfect sendoff to them, but neither does it tarnish their legacy.
(And the final moment after the credits made me say, "HA!" Somehow, I think that if this movie succeeds, it won't be the last.)