I would definitely take part 
in such a contest. Certainly, it would be popular among the forum users, but not among players.
For years I have organized contests in MMO games for my Guilds / Clans / Allies / Servers. Every time, among the 100-500 players who could participate storytelling, only 3-5 signed up in 1-2 months. But when I was doing the quick āwho will find me will get a prizeā contest, 10 people immediately applied.
The best (most popular) gaming contests are those that happen inside the game. Do you remember the animation (emote) contest in Conan 
The idea was cool, but its course had too little to do with the game (not counting other problems).
I give a 
for the idea and send my application for the contest, ha ha! 
If the contest were to take place, I would add that submissions must be posted on the forum. It would be a pity to be able to read only a few of the winners.