I realise that I misremembered something. I blame it on being very busy today and happening upon this all of a sudden when I came to vote on the monthly poll, and then in my enthusiasm trying to think through and post quickly on limited time.
Today I was thinking that we'd already voted like this last year (after a longer and more complicated pre-vote process) and had had this result when in fact we voted only on the process and chose to keep the categories the same. My memories of the twelve separate category nomination threads from a previous year were blurring with it and our discussion a while ago on how to approach next year. Now understanding better, I am fully in support of proceeding in exactly the way Tom first suggested (not that it matters since we're doing it anyway but I wanted to clarify my opinion). I think it's a great idea and am excited to see how it turns out.
ETA-Also, thinking through it I'm with issybird and Dazrin on 6. It would be easier for Tom since it would be less votes from each person to keep up with and as Dazrin says it would force people to support the categories they most want.