I think you could go a bit further than that, even. Make it a top 16 / 32 contest, let people nominate their favorite games of the year, then put them into a bracket. You could do the whole nomination / bracket predicting phase in December, then throw up the contest at the beginning of January. You're always getting new games, so it keeps things fresh.
--
"When I was a young man, I had liberty, but I did not see it. I had time, but I did not know it."