For those that missed out on the Direct2Drive deal or don't want to risk the Russian VPN option with Cdkeyshere.com Gametap seems to be the next cheapest option at $54.95US. At the moment it doesn't mention that its a Pre-Order but once you place your order it gives the following message:
You'll receive your download links and activation code by email the 11/09/2010 at 07:00 PST
See here to get this in your time zone.
http://www.wolframalpha.com/input/?i=09/11/2010+07:00+PST
Its 11PM tonight for Perth.
This is 8% cheaper than buying from the steam US or UK stores which I couldn't get to work anyway. I haven't used gametap before but they look reputable.
You need to use a VPN (Virtual Private Network) to get the US/UK Steam stores to work.