A Windows 7 build with version number 6.1.7000 was leaked to the web last week and is being widely pirated as you read this. Consensus is that this is the build Microsoft will release early in 2009 as a beta. A post today in the Engineering Windows 7 blog gives us another hint that this is, in fact, the beta.
"Like many places we’ve spent the past few weeks under quite a bit of snow, which is pretty unusual for Seattle! Most of us on the team took advantage of the snow time to install test builds of Windows 7 on our home machines as we finalize the beta for early 2009—I know I felt like I installed it on 7000 different machines. We’re definitely looking forward to seeing folks kick the tires on the beta when it is available. For more information on the beta, please stay tuned to http://www.microsoft.com/windows/windows-7 which is where we will post information about participation."