I have win7 64 bit and I am experiencing the same problem. The speech recognition windows program picks up just fine, but for some reason Pilfius does not generate the keystrokes. I have tried just about every program I can get my hands on, and so far nothing either works, or just doesn't compare to Pilfius.
To scream the obvious again: SOMEONE PLEASE HELP US 64 BIT USERS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!