Check the link! Halo for PC
Now all you "I want Halo on PC" bloodsuckers can finally quiet down!
*EDIT* I strongly suggest you read the whole article, but if you're too lazy, the important parts are:
-PC version: Gearbox Software (Half-Life: Opposing Forces).
-Macintosh version: Westlake Interactive (Mac ports of Deus Ex, Unreal Tournament, and more).
-Release Date : "Summer 2003" for the PC, just "2003" for the Mac.
And, "Additional information regarding game content, features and enhancements will be announced at a later date".
Thanks HBO for the heads up!
*EDIT2* Found this fake pic at T&R: