SPOILER: A scene appears after the closing credits: Dr MacTaggart checks up on her comatose patient, and discovers Professor Xavier transferred his mind into the patient's body.
The Marvel logo features comic-book images of the X-Men in its pages. Notable characters/events seen are the Phoenix, Angel, Juggernaut, and a moving bridge.
When the 20th Century Fox logo fades away, the X in the logo stays for a second longer before it also fades away.
The X-Films' title sequences features a weapon used by the villain of each film, backed by the X-Men's Cerebro device.
In this film it is a sample of Leech's mutant-neutralizing blood.