Thank you everyone for the input. While some of the entries are very obvious, we will investigate once the contest is over and disqualify any cheaters. We don't want to reveal too much details, but be assured that we will investigate the winners closely.
In meanwhile, let's give some of the contestants the benefit of the doubt. They may have a large fan base hidden somewhere, or they might have spread their videos on multiple forums, so anything is possible. A contest like this will get competitive very fast, let's not point fingers at each other too quick.