Big Pot w/ Overs: Odds to Peel?

[nnphoenix]

Button sat down 2 hands ago, so no real read. CO is about 65/28 over 200ish hands.

Full Tilt 1/2 Hold'em (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Preflop: Hero is MP2 with K, Q.
2 folds, Hero raises, CO calls, Button 3-bets, 2 folds, Hero calls, CO calls.

Flop: (10.50 SB) 3, 9, 6 3 players)
Hero checks, CO checks, Button bets, Hero ???

Getting 11½:1 on my call, but there's a strong possibility my outs are no good, and maniac CO has yet to act.

Do I take another card here, or flush it?