Like half the world, i have been trying to download Windows 7 tonight. I might have found a legitimate link, thanks to @benhedrington – i clicked this and it started downloading something. It obviously comes from download.microsoft.com and it begins with the number 7000, which i suppose is a good sign.
Update: Steve Clayton corroborates this link, and also provides a 64-bit link:
Let’s hope it’s the right thing, hey!
I think we also need an activation key, otherwise it will only work for 30 days. I managed to submit my email address on the technet beta program signup, so hopefully they will send me one.