Jon's commented on the PC release of Braid:
At this time, we’re looking at a window of February-March 2009 for the PC
I also liked this little addition from him in the comment thread when asked if it was releasing on Steam:
"Oh, and about Steam: Originally they did not seem very interested in Braid, but
now that it’s a successful game they seem to have changed their mind. I haven’t
signed a contract with them, but they seem interested, so the biggest factor now
is just me finishing the PC version and giving it to them."