Yep the testing public beta has been released but with no warranties whatsoever. This is to only mass test the OS on people machines and then gather feedback from them before the actual release.
It's a good way of hooking up fish before throwing the net
Public betas are also a good way of finding out how badly users are able to screw things up!
If you're comfortable installing a second OS on your computer (don't get rid of your current one) and would like to see what Windows 7 is like, give it a go. If you're not very computer-savvy or don't have a spare computer, you probably don't want to risk it.
