$6.5 bubble, weird villain play...

[kuey]

This one got me thinking a bit as the villain hasn't shown anything weird like this before. I haven't seen him limp a hand since early in the tournament, so I didn't shove PF. I normally would've bet the flop, but again villain kind of threw me off guard here.

PokerStars Tournament, Big Blind is t400 with t25 antes (4 handed) Converter on pregopoker.com

CO (t2435)
Button (t5245)
SB (t2955)
Hero (t2865)

Preflop: Hero is in BB with 5[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/diamond.gif[/img]
CO calls t400, <font color="gray">Button folds</font>, <font color="gray">SB folds</font>, Hero checks

Flop: (t1100) A[img]/images/graemlins/heart.gif[/img] 3[img]/images/graemlins/spade.gif[/img] 6[img]/images/graemlins/diamond.gif[/img] (2 players)
Hero checks, CO checks

Turn: (t1100) Q[img]/images/graemlins/heart.gif[/img] (2 players)
Hero checks, <font color="red">CO bets t2010 (All-in)</font>, Hero ???

What about the villain's bet here. It seems like he just hit a Q, or had a big pair or something. Is it okay to call here or should I let it go?