Is betting the river here a spew or value ?

[BubbleMint]

Button is a total donkey, spewing like crazy. Likes to bluff raise in weird spots. Has been playing any two suited, often thinks one pair is good.

No reads on BB. Him lead 3 betting shows strength, but then the check on the river made me think maybe a counterfeited 87.
The table had been 3 betting and capping draws, so maybe he has lumped me in with the donks and fighting back light ?

Full Tilt 3/6 Hold'em (8 handed) Full Tilt Converter Tool from FlopTurnRiver.com (Format: 2+2 Forums)

Preflop: Hero is CO with A[img]/images/graemlins/club.gif[/img], A[img]/images/graemlins/heart.gif[/img].
<font color="#666666">3 folds</font>, MP2 calls, <font color="#CC3333">Hero raises</font>, Button calls, <font color="#666666">1 fold</font>, BB calls, MP2 calls.

Flop: (8.50 SB) 8[img]/images/graemlins/spade.gif[/img], 4[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(4 players)</font>
BB checks, MP2 checks, <font color="#CC3333">Hero bets</font>, Button calls, BB calls, MP2 calls.

Turn: (6.25 BB) 9[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(4 players)</font>
<font color="#CC3333">BB bets</font>, MP2 calls, <font color="#CC3333">Hero raises</font>, Button calls, <font color="#CC3333">BB 3-bets</font>, MP2 folds, Hero calls, Button calls.

River: (17.25 BB) 9[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, <font color="#CC3333">Hero bets</font>

My intention is to b/f