The Beta for Windows 7 is officially launched this week.
For TechNet subscribers, you can download Windows 7 Beta now here. On January 9th, the beta will open to all IT professionals on the Springboard Series for Windows 7 here.
Full details are available on the Springboard blog.
Steve Ballmer announced during his CES keynote the immediate availability of the Windows 7 beta to TechNet
Yes, TechNet subscribers can get the download from http://technet.microsoft.com/subscriptions/dd180822.aspx