OK, it’s time! Go get it before it’s gone!
http://technet.microsoft.com/en-us/evalcenter/dd353205.aspx – The site is running VERY slow, but be patient, there are 2.5 million people trying to get it too… 
Beta expires on August 1, 2009, so have fun!
** Update **
The official Windows 7 beta download link is still down, but Lifehacker has managed to track down the direct download links to the 32-bit and 64-bit version. [Microsoft]
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