Windows 7 requires a product activation after 30 days, therefore you are going to need a beta key sooner or later. Here, I describe two ways how to activate Windows 7.
Should you be a TechNET subscriber then you can easily retrieve a beta key for Windows 7 from Microsoft.
You won’t get an official beta key easily, that’s why you could use TimerNuke to bypass the Windows 7 product activation. This little tool will remove the services that make a product activation necessary for both editions x32 and x64.