River Shove... 1/2nl Call or Fold?

[Diggity D]

Hardly any info on villian... I had only been sitting with him for 40 or so hands.

I was a little thrown off by his near pot sized bets on the flop, and especially the turn. Felt to me like he was trying to bet me off of a flush draw... Then the flush hits the river and he shoves?

What are your thoughts?

PokerStars Game #12179456816: Hold'em No Limit ($1/$2) - 2007/09/21 - 02:36:51 (ET)
Table 'Rarahu' 9-max Seat #3 is the button
Seat 1: Babs1337 ($421.50 in chips)
Seat 2: Diggity D ($389.55 in chips)
Seat 3: Ufearme44 ($340.95 in chips)
Seat 4: itchy333 ($260.40 in chips)
Seat 5: mike8557 ($200 in chips)
Seat 6: treysfull21 ($208.25 in chips)
Seat 7: Turbothomsen ($217.50 in chips)
Seat 8: GMAN09 ($227.25 in chips)
Seat 9: dymarko ($24.70 in chips)
itchy333: posts small blind $1
mike8557: posts big blind $2
*** HOLE CARDS ***
Dealt to Diggity D [Kh 9h]
treysfull21: folds
Turbothomsen: folds
GMAN09: raises $4 to $6
dymarko: folds
Babs1337: folds
Diggity D: calls $6
Ufearme44: folds
itchy333: calls $5
mike8557: folds
*** FLOP *** [9c Kd 6d]
itchy333: bets $20
GMAN09: folds
Diggity D: calls $20
*** TURN *** [9c Kd 6d] [4s]
itchy333: bets $64
Diggity D: calls $64
*** RIVER *** [9c Kd 6d 4s] [8d]
itchy333: bets $170.40 and is all-in
Diggity D: ?