Stand? Yes. Deliver? Mostly.
Comics are comics and movies are movies, and no matter how frequently or completely they have merged in the last couple of years, there is nothing like a movie like X-Men: The Last Stand to remind you of that fact. As Internet gossip, a large chunk of the advertising, and even the title has suggested, X3 comes with heavy body count, including several heavy hitters from the trilogy's main cast. I won't spoil any of that but here's an easy hint: take a look at any billboard for the film. Observe which characters appear in said billboards. Now, consider which ones do not. Booyah.
Comic books are soap operas in spandex. They are infinite stories. The only thing that ends a serialized super-hero comic is poor sales, and for the better part of three decades, The X-Men and their affiliated titles have been the crown jewel for Marvel Comics. Writers and artists may come and go, but in the comics industry, mutants are forever.
To keep people watching soap operas and reading comics, things have to be continually stirred up, but not so stirred up that they can't be unstirred and put back to normal so that the property can continue on forever. In soap operas, characters get married and divorced to keep things interesting. In comics, characters die. The seemingly concrete state of eternal not-livingness would seem a strange choice for a recurring plot point, but in comics, where characters are essentially living gods, mortality is not exactly hard and fast. Superman is only the most famous example; the number of comic book heroes and villains who've died and been reborn number in the hundreds.
The X-Man Jean Grey knows the illusion of change all too well. Originally known by the codename Marvel Girl, when she first received the name Phoenix, in October of 1976, it was to reflect the fact that Grey gave her life to save her teammates, only to be seemingly reborn with a massive boost in powers. Thirty years on, the Phoenix monicker seems more like a cruel joke: Grey's had more lives than a cat. Wikipedia tells me that Susan Lucci's Erica Kane, a mainstay of soap All My Children since 1970, has been married ten times. Jean Grey's probably died about that many times over nearly the exact same time frame. Unless something's change in the last couple months (I'm not really a regular X-Men reader), she's currently dead, but you'd be a fool if you believed that would last more than, oh, six to eight more months.
So how do we reconcile the major deaths in X-Men: The Last Stand? As a movie fan, who is constantly frustrated by movies in which characters (who can't fly or shoot energy beams out of their eyes) overcome impossible odds without so much as scratching their chin, it's refreshing to see an action film that isn't afraid to raise the stakes, to create a real sense of danger, to toss the audience for an emotional loop. As a comic book fan fine, a comic book nerd it's disappointing to see characters with thirty years of baggage (from another medium, mind you) wiped out in a brief scene in the first act of a Brett Ratner movie. And even if Grey's first cinematic rebirth features prominently in The Last Stand, the film's other deaths don't seem very reversibile: comic deaths tend to be of the nebulous we-never-found-the-body variety; the movie's scattering-your-atoms-into-dust-floating-in-the-wind type deaths are a bit more concrete.
In the comics, all the mutants get to pop up in the half-dozen (or more) X-Men books that are perpetually on the stands. Movies only get one two-hour crack at these things once every three years, if they're lucky. X-Men was groaning under the weight of too many characters; even though heavy hitters get the hook early on, Ratner barely has time to provide cursory development to new cast members Angel, Leech, Kitty Pride, or Beast. Under the direction of Bryan Singer, the X-Men films felt like blockbusters that were about characters first and action second. That's not the case with The Last Stand, which has some brilliant set pieces, a couple cute or touching moments (all that require an extensive knowledge of the previous movies, if not decades of comics to appreciate), and a whole lot of "Is there a scene missing?"s and "Is he really dead?"s and "Why didn't they just try the cure on her?"s.
It's almost like the movie doesn't have time for all its characters, so no bigs if it puts the kaibosh on some of them. Besides, with those expensive star salaries and special effects, these X-Men movies are getting cost prohibitive. But wait X3 just made over $100 million in a single weekend. There's no way Fox is going to let the series out to pasture now. With that sort of drawing power, you might not see them so quick to kill off their cast cash cows in the future.