Michael J Bassett just revealed on his Twitter that Silent Hill: Revelation may very well be making an appearance at Comic Con next month. Hopefully, this will mean we'll be seeing a trailer and/or a poster around that time.
Another update: Bassett and Clemens will spend all day Saturday answering questions about Revelation. At 12:45, 2 clips will be shown, one featuring a new monster. No trailer will be shown, as the producers are planning to wait a few more weeks before they release it.