They pulled few punches in this one, and were clearly bent on kicking it up a notch from the previous movies. Again, it works.
Special Effects: 9 out of 10- they're solid, and have some pretty creative devastation. Hard core.
Babe Factor (Yeah, I'm a guy. Deal.): 7 out of 10- Mercury, er, Rebecca Romijn does nudity like she was born that way. ;-) Famke Janssen proves once and for all that redheads are hot (and NOT to be trifled with!). Anna Paquin is absolutely adorable. Halle Berry is hot as always, though she seems a bit more low-key than usual (probably as penance for Catwoman).
Of course, the more well-versed you are with the comics the more you'll pick out the little details here. I have only a casual familiarity with them, but was still able to pick out a few little bits here and there.
Patrick Stewart and Ian McKellen rock, and the interplay between them is always interesting.
One other thing. As with X-Men 2, there's a short bit after the closing credits. Now you know.
Special note for queenwench: there's a trailer for Snakes on a Plane!!!