(I play protoss, obv.

Protoss vs Terran: 12 wins 9 losses
Protoss vs Protoss: 14 wins 9 losses
Protoss vs Zerg: 17 wins 14 losses
1 win due to instant surrender by enemy
Total: 44 wins 32 losses, 996 ranking masters league
It seems that my win ratios aren't too far from each other vs each race (of course the sample size is small, though...), though I interestingly played versus zerg a lot more than vs protoss or terran.
On a side note, I believe I will be switching to random for season 5, I want dem cool portraits, though I could drop to diamond

a couple of replays:
http://rts-sanctuary.com/index.php?port ... pic=210145
http://rts-sanctuary.com/index.php?port ... pic=210146