No read on villian sat down about an orbit ago. Is the check on turn and river ok or should I be value betting the river?

Texas Hold'em $0.25-$0.25 NL (Real Money), #495,317,895
Table Odense, 17 May 2006 11:30 PM ET
Seat 1: FishMustDie ($12.20 in chips)
Seat 2: bbgun200 ($21.15 in chips)
Seat 3: AmbeyentFyre ($79.65 in chips)
Seat 4: xS2x ($6.25 in chips)
Seat 5: Net9965 ($4.95 in chips)
Seat 6: OU BAMF ($24.60 in chips)
Seat 7: ProZach0 ($27.30 in chips) [ 8D,8S ]
Seat 8: Windsor x ($97.55 in chips)
Seat 9: Cheftic ($39.40 in chips)
Seat 10: AmyW0220 ($24.50 in chips)
ANTES/BLINDS
Cheftic posts blind ($0.15), AmyW0220 posts blind ($0.25).

PRE-FLOP
FishMustDie folds, bbgun200 calls $0.25, AmbeyentFyre folds, xS2x folds, Net9965 folds, OU BAMF calls $0.25, ProZach0 calls $0.25, Windsor x folds, Cheftic calls $0.10, AmyW0220 checks.

FLOP [board cards 8C,7S,9H ]
Cheftic bets $1.50, AmyW0220 folds, bbgun200 folds, OU BAMF folds, ProZach0 bets $4, Cheftic calls $2.50.

TURN [board cards 8C,7S,9H,6D ]
Cheftic checks, ProZach0 checks.

RIVER [board cards 8C,7S,9H,6D,AD ]
Cheftic checks, ProZach0 checks.

SHOWDOWN
Cheftic shows [ 9S,4H ]
ProZach0 shows [ 8D,8S ]
ProZach0 wins $8.75.
SUMMARY
Dealer: Windsor x
Pot: $9.25, (including rake: $0.50)
bbgun200, loses $0.25
OU BAMF, loses $0.25
ProZach0, bets $4.25, collects $8.75, net $4.50
Cheftic, loses $4.25
AmyW0220, loses $0.25