Easter egg: Go to scenes, and go to the screen for scenes 10-12. In the lower right corner will be a small X. Highlight it and press enter for an extended scene with Beast reciting Shakespeare.
Easter egg: Under Join the Brotherhood (Magneto's side) Go to Features. Then Deleted Scenes. Press "More" until you find the scene called "Henry Warns About Magneto". Highlight it, then press the left arrow to highlight an "X". Press enter and you will get to watch a short 2005 promo for the movie. Under Take a Stand (X-men side), this feature requires you to highlight "X-men land the chopter" then press the left arrow to highlight a "Magneto Symbol".
Easter egg: On the Region 4 (and possibly other regions) DVD, the deleted scenes are different depending on whether you choose 'Join the Brotherhood' or 'Take a Stand', so try both.
Chosen answer: The piece did move, very very slightly. I'd argue that the cure is generally permanent, but perhaps with someone of Magneto's power the X gene can't be permanently suppressed, and will slowly regenerate itself through his body, gradually restoring him to full strength.
Jon Sandys