Stage downstairs, vodka up.

I suggest upstairs. I haven't seen any poetry sessions downstairs (part of the bar upstairs), but the KGB Bar receives my two thumbs up. Drinks are strong, cheap, and plentiful. On a "busy" Saturday night in the 'hood, the KGB's patrons are a non-pretentious bunch too busy in their own conversations to care about being seen (read: this is a good thing). Read about the bar's history here and reviews there. Cheers.