The following deleted scenes are ALL on the U.S. DVD , as far as I know:
(from SuperHeroHype.com)
1) Xavier Voice-Over For Main Titles
Continuing the tradition of the first two films, a chunk of exposition. Dropped because it was deemed superfluous. (I don't think this is the same speech as the one he gives in the trailer.)
2) Alternate Version: Beast Meets Logan
A slightly more antagonistic first encounter between Wolverine and Beast.
3) Jimmy in Laboratory
Shots of Leech being scanned, and various scientific bits of equipment being used to create the cure.
4) Plastic Weapons Manufacturing
Shots of soldiers manufacturing the plastic guns used in the final battle.
5) Pyro Tells Magneto About The Cure Announcement - Clean Shaven Version
Short "They just announced it!" scene between Pyro and Magneto.
6) Pyro Tells Magneto About The Cure Announcement - Bearded Version
A different version of the same scene, only with a bearded Gandalf - err - Magneto.
7) Alternate Version: Guard Yells at The President
A more expressive version of the scene where the imprisoned Mystique impersonates the President: "Mr President, shut the **** up!"
8) Extended Fight Sequence at Jean Grey's House:
A much more brutal version of the scene where Wolverine and Storm try to get into Jean's house. This includes more Wolverine and Juggernaut mano e mano, and a nice bit of business where Logan becomes a conduit to channel Storm's electrical energy into Juggernaut. Cut because it was "too long".
9) "Psychic Battle" Voices:
During the Phoenix/Professor house sequence, Xavier mentally pleads with Jean to stop, but she says that she is the Phoenix (I think there's an alternate head-on angle of Xavier's POV at Jean. I think it also has temp sound.)
10) Original Version: Jean Displays Her Power at the Encampment:
Jean takes a coffee cup and turns it into a miniature sun, blowing rays of heat at the Brotherhood camp. I liked this scene, as it showed she has greater control of her powers.
11) Alternate Version: Bobby and Kitty Skate
A "controversial" version of the skating scene, only this time they kiss, adding more of an incentive for Rogue's actions later in the film.
12) Hank Warns Trask of Magneto's Plan
As the military prepare to enter Magneto's forest hideout, Hank calls to warn them that Magneto may be preparing an attack elsewhere.
13) Original Version: X-Men Board The Jet
A different version of the rallying scene between Wolverine and Iceman, shifting the emphasis to Iceman. Some of this version appeared in one of the trailers.
14) Jean Senses a Scared Little Girl
An extension to the scene where a family, trapped in their car on the bridge, encounter Magneto. It also helped take the scene from daylight to dusk - it was cinematographer Dante Spinotti's favourite scene of the film.
15) Wave!
An addition to the attack on Alcatraz - Storm creates a deluge, to fend off a wave of attacking Brotherhood members.
16) Bobby vs. Phat:
Remember the fat mutant at the church meeting, who shrank down in size so he could sit down? Well, here he returns, during the Alcatraz attack, where he is brought down by Iceman and Colossus. This scene was cut because it wasn't well-executed. (Really? Lame excuse.)
17) Beast Breaks a Neck
Cut to ensure a PG-13 rating.
18) Magneto Asks Jean To Help In The Battle
A nice addition to the Alcatraz attack: Magneto sees that some of his pawns are being cut down by cure weapons, and demands that Jean step in to help. "You sound like him again", she observes, referring to Xavier.
19) Alternate Version: Here's Juggy
A version of the scene where Juggernaut enters Leech's cell, with dialogue paying tribute to The Shining.
20) Magneto Tortures Logan
Slightly extended version of the "You never learn" torture scene.
21) Extended Dark Phoenix Destruction: Consists mostly of an extended tracking shot of the facility and soldiers getting blown up. Why didn't they use this in the final film?
22) Alternate Ending: Rogue Returns
A gloved version of the scene where Bobby greets Rogue on her return to the school...
23) Alternate Ending: New School Year Begins
Shows Hank returning to teach at Xavier's school, instead of taking on the Ambassador's job.
24) Wolverine going back to Canada for some reason Logan Returns to Canada
There's still a bunch of stuff that hasn't (or won't) be released. There's an article that mentions the actress who played Psylocke (and the work she did in the film) here, and there's still all the stuff from the original post that never got in.
And wait until you get a load of what the reasons for cutting the scenes were. Try reading this page and this as well.