Looking at Rage from Id, it is clear consoles pack some power - in the case of Rage both the 360 and PC version are running at 60fps, however it was not stated what the system was for the PC. Rage and AW look downright amazing.
AW was going to be a Vista only title, when it was announced for PC, now we have Win7 in a few days (along with it being for 360 that is). DirectX 11 hardware is around the corner as well. But now look at the PC game market, while it is not dead, it has many issues. And it is dominated by MMO's and Sims, seems we will have MMO's soon enough on the 360 as well - so what will that do to the already embattled PC market. Other signs pointing to Nvidia concentrating more on other things, may well see ATI and Intel left to battle the PC GPU market. But then again the upcoming Nvidia chips are more akin to Intel's Larrabee than anything else (rumors are still around for Larrabee to be in the next console). Nvidia is going where the money is, and also attacking Intel on a new front (mobile with the Ion, and Tegra(think Zune processor), etc. An amazing amount has changed in the PC market in a small amount of time (been a while since that happened), and while the dev cycle went on for AW I am sure it made sense that for now 360 only was the way to go. Then after getting it out the door, see what the PC market is and work on a port. And who knows, some articles still say it is coming to PC, others say delayed, some say nothing is known.
It makes sense to concentrate on a known system that will sell hopefully for Remedy millions of copies. On the PC we already know about piracy issues, and a small team like Remedy that has poured sweat, blood, and tears deserves to have their game purchased (not copies from a table in the local market in some small country). They are a very talented team, and deserve well for their efforts.
Additionally, maybe the 360 will be cheaper again when AW is ready to go, so that could be a bonus for those on the fence waiting to buy a console.
Check the threads over at the AW forums, you might find better info on what is going on, I have not looked in a few weeks.
Talryyn Games