I've anxiously been awaiting this game too, however I'm not a big fan of Steam downloads and won't spend my money until the box hits stores. Only problem is, there doesn't seem to be any indication of when the PC box will be available unless I missed it somewhere, so far all I can find is this blurp from formula1-game.com.
"F1 2010 is now shipping to retail stores in North America and will release across mainland Europe and PAL territories on Thursday 23rd September with a UK street date on Friday 24th September for the Xbox 360® video game and entertainment system from Microsoft®, PlayStation®3 (PS3™) computer entertainment system and
PC Games for Windows®; the PC edition is also available as a digital download from multiple online services."
This youtube vid is pretty cool
YouTube - F1 2010 PC Test
Edit: I've looked everywhere (FS, BB, GS etc.) and I can't find a single source showing the PC disk even being avaliable, they all show Xbox and PS3 but no PC!..wtf!