JJ underpair against uberfish...
 

Button is fishy over 100 hands. around 48/5
Party Poker 3/6 Hold'em (9 handed) converter

Preflop: Hero is MP2 with J[img]/images/graemlins/spade.gif[/img], J[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">3 folds</font>, <font color="#CC3333">Hero raises</font>, <font color="#666666">2 folds</font>, Button calls, <font color="#666666">2 folds</font>.

Flop: (5.33 SB) K[img]/images/graemlins/spade.gif[/img], 8[img]/images/graemlins/diamond.gif[/img], Q[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

Turn: (3.66 BB) 7[img]/images/graemlins/club.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

River: (5.66 BB) 7[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

Final Pot: 7.66 BB

Standard ?

Re: JJ underpair against uberfish...
 

Standard. (One might argue that the river bet is thin, but a bet/fold is superior to the alternative, which isn't check/call but check/fold against a fish. Well, this is based on his unstated postflop aggression being in line with his preflop stats.)

Re: JJ underpair against uberfish...
 

Villain's Went to Showdown Rate would be a much more useful tool in deciding a river value bet.