Well, if we did that, I would judge it, I suppose. The charts could also end up seeing print in the eventually-published "Forward... to Adventure! Gamemaster's Notebook" (a.k.a. "FtA!GN").
Of course, if it was going to be for FtA! the rules would require that ALL tables be devisable on D6 rolls only.
For the prizes, I would guess "equivalent Flying Mice PDF"; since the idea would be most of the winners would already have FtA! at least on PDF. The print copy is still a good prize. On top of that, the winners plus possibly other contestants might end up seeing their name in the credits of the FtA!GN sourcebook when it is released.
RPGPundit
PS: I know a lot of people don't exactly think of me as "Impartial", but dude, we're talking about me in the role of Game Designer here, judging the creation of Random Tables for an Old School RPG. I don't care if Ron Fucking Edwards himself wrote the best Random Monster Weakness Chart I ever saw, as long as its the best, and its something good and old school (extra points if it emulates Nethack!), then I'd give the man the prize.