50nl - Top 2 in multiway pot deep gets 3-bet on drawy board

[ddrstel]

Villain is 50/5/4 over 50 hands, my image is TAG, maybe slightly on the nitty side.

Full Tilt Poker - No Limit Hold'em Cash Game - $0.25/$0.50 Blinds - 6 Players - (LegoPoker Hand History Converter)

SB: $73.65
BB: $19.15
UTG: $80.45
MP: $80.90
CO: $26.00
Hero (BTN): $87.55

CO posts $0.50
Preflop: Hero is dealt Q[img]/images/graemlins/club.gif[/img] 9[img]/images/graemlins/diamond.gif[/img] (6 Players)
UTG folds, MP calls $0.50, CO checks, Hero calls $0.50, SB folds, <font color="red">BB raises to $1.50</font>, MP calls $1.00, CO calls $1.00, Hero calls $1.00

Flop: ($6.25) Q[img]/images/graemlins/diamond.gif[/img] 7[img]/images/graemlins/spade.gif[/img] 9[img]/images/graemlins/spade.gif[/img] (4 Players)
BB checks, <font color="red">MP bets $3.00</font>, CO folds, <font color="red">Hero raises to $12.50</font>, BB folds, <font color="red">MP raises all-in to $79.40</font>, Hero...?