Silent Hill: Revelation 3D will not suffer a lack of continuity. It looks like new stars Adelaide Clemens and Kit Harington will have some company. Original stars Radha Mitchell, Sean Bean, and Deborah Kara Unger have signed on to return for the sequel. It's unclear whether their roles will be as large the second time around or if they'll appear just long enough to be skinned alive.

Director Michael J. Bassett says via press release:
It wouldn’t be the same without some of the original Silent Hill cast.  Sean, Radha and Deborah’s return will certainly thrill fans of the franchise and compliment Revelations stars Adelaide and Kit.

Oh good. They're making the same movie. Just as suspected. I was concerned I would have to think. Phew!