Commenting contest what do you think?

As you know I have giveaway over soon, I am thinking of commenting contest at my blog. What do you think? The commenting could be like be the first to comment in my blog post, or the person with most comment in my blog posts. Hm... I am thinking which is better. Of course there is prize for winner.

Sound like it is top commentator of the month will win? Perhaps post up the prize to attract people who has interest to comment and win? What your say?