Saw that trailer about a month ago and really didn't know what to think. Read some reviews which totally gave away the premise/surprise. I might still check it out.
The filmmakers have also received some criticism with claims that it's staged and not a documentary. It all contributes to more publicity though, which can't be a bad thing for an independent film.
If one watches the trailer and then reads the Wikipedia article, or any article describing the movie, it's assumed these articles have included spoilers. Perhaps the trailer really is misleading.
Panasonic TH-42PE7U plasma, Toshiba HD-D3, PS3, Shaw DCX3400, Yamaha HTR-6160, Polk 6.1, Belkin PF30, Harmony 700