Saw this on the weekend and it was simply ok. Nothing new that hadn't been done before (see a film called funny games with tim roth far superior to this). The shocks weren't shocking enough. The worst thing was the cover - to put Stephen Moyer and Anna Paquin on it as if they starred in it was very misleading by the film maker, they were only it between them for 10 minutes of the just under and hour and a half - that was the only reason I bought it!! I think Anna's brother directed this as his surname was the same as hers(that's probably why they were in the film).
There are other films of this genre (as in funny games) that are far superior to this one.