SimonG: Btw, gfwl didn't gave me any problems what so ever, I even bought Gears of War via an irish vpn from the MS Marketplace (before the relaunch).
Oh, and I have heard (yet never tried), you can get your account in germany registered as an US account (with dollars and everything), if you can convince steam support that you are an american serviceman living in Germany. But I never tried that, so it just might be BS ...
Yeah, I've never had a problem with GFWL in that sense. My copy of Dead Rising 2 I got from GamersGate unlocked on the US release date no problems and that didn't get a local PC release to the best of my knowledge.
As for your second comment, I've heard several people mention that Valve can lock the store to your billing address region. Although I'm not sure if they still offer such a service. Not that I'd use it. If I were to ever get a US billing address, etc., I'd just make a new account and then gift to my current one and use a US VPN, etc. to "unlock" the games...