NL100: 99 makes boat on turn. 2nd barrell or slowplay here?

[AlexB182]

This was at the beginning of the session, after 20 hands he was at 40/1.7/1.2.
I was running at 16/12, can't imagine he is not viewing me as a TAG so far.

I hit my two outer on the turn here but I'm pretty sure villain does not have too much of a hand here, I put him either on a weak J (JT,QJ stuff) or on a medium pair (88,77), I think there is also a small chance that he is floating me with nothing here or overs only. I don't think giving a free card here would be a problem (if a J comes off I might get tricky but I have no problem letting him draw to 2 outs) but I don't want to lose value in case he would be calling me down with TPGK type of hands. On the other hand, checking behind here might induce him to fire at the pot on the river if he puts me on a hand like AK, AQ and thinks I gave up after the usual CB.
All comments appreciated!

Full Tilt Poker, $0.50/$1 NL Hold'em Cash Game, 8 Players
LeggoPoker.com - Hand History Converter

BB: $171
UTG: $118.55
UTG+1: $37.45
Hero (MP1): $95
MP2: $43.75
CO: $97.50
BTN: $100.90
SB: $194.55

Pre-Flop: 9[img]/images/graemlins/spade.gif[/img] 9[img]/images/graemlins/club.gif[/img] dealt to Hero (MP1)
2 folds, <font color="red">Hero raises to $4</font>, 2 folds, BTN calls $4, SB folds, BB calls $3

Flop: ($12.50) 6[img]/images/graemlins/heart.gif[/img] J[img]/images/graemlins/club.gif[/img] 6[img]/images/graemlins/spade.gif[/img] (3 Players)
BB checks, <font color="red">Hero bets $9.50</font>, BTN folds, BB calls $9.50

Turn: ($31.50) 9[img]/images/graemlins/heart.gif[/img] (2 Players)
BB checks, <font color="red">Hero ?