As per the Vista team blog, Microsoft announced that attendees to the Microsoft PDC conference in October will recieve an advance preview copy of Windows 7 on a USB drive. This is a great opportunity for developers to get a jumpstart on Windows 7.
Some of us more infrastructure-oriented types might want to check out PDC for this opportunity as well. Microsoft has been very tight-lipped on Windows 7 and any rumor blog or screenshots I've heard about have been taken down almost immediately. I know I may be in the minority, but I think it's the right thing to so. If it were ready for public consumption then it would be out there. Especially with the anti-vista sentiment, despite the Windows mojave project, and the general enterprise sentiment of "We'll wait for Windows 7" keeping it under wraps until it's "ready" benefits everyone. I believe Microsoft will release a solid, "ready for market" product with Windows 7.
Check out the PDC site to sign up - http://www.microsoftpdc.com/
PCWorld has been pretty good at collating rumors lately and has the definitive Windows 7 post here. Be sure to check out the latest NetworkWorld article on Windows 7 from John Fontana as well
Before anyone asks, I know nothing of Windows 7 except what's been explicitly posted on an official Microsoft site. I have thoughts and conjectures just like everyone else. Feel free to post yours below. :)