HALO 3 for PC

There has been much stir about HALO 3 being ported to PC. The closest estimate I have seen is Sept 2009. That would be great. The outside time frame I have read is sometime in 2013. That would suck! HALO WARS maybe ported for PC before 2013. I don't see Bungie missing out on the additional revenue. Of course, it is all up to Microsoft. At any rate, the sooner the better.