sweet. this saves all the effort of getting a VPN just to buy steam games from the US/UK. always fun to see what
http://www.steamprices.com/au/topripoffs looks like before i hit the buy button. saved $50 on DXHR that way. /bookmarked
as for MW3, it's just expensive in time/money/effort. for me it's $99 USD in AU Steam, but $59 USD, 6.6BTC for a game i likely won't be playing until 2012 (would be dealing with SWTOR, BF3, xmas, relatives, in random order), and also there's no preorder bonuses, no discounts, and more than likely i'd get bumped into waiting 2 days for the unlock (regional unlocks are staggered, it's worse elsewhere, i think JP still has to wait)
even if i buy it from the US store, MW has always been awful to buy through steam + for the same price, there's RAGE, skyrim, and other games.
i.e.
http://www.steamprices.com/au/search?modern+warfare and
http://www.steamprices.com/au/upcoming?p=2