Is it too late for me to give a little input on WPC? If so, then please feel free to ignore this post!
The problem I see with voting is that, while it may have a respectable amount of voters in the beginning, inevitably, the numbers will taper off until it's a meager few. It's similar to what happened in the old rom hack of the week voting, and what's happening (in a way) with the recent game of the month in the game dev forum. The only way I can see getting around it would be to require a certain number of votes to pick a winner (first to 5 or something for example), but that, of course, poses its own problems.
I personally like the way that the judging was done on the pixel contest for PCX, where the judges scored the sprites based on the individual categories, and showed what they rated each part. Transparency, I believe, would clear any sort of cries of bias or any other uncomfortableness surrounding a set judge, especially if said judges explained their scores when prompted.