Hello!
http://ie.microsoft.com/testdrive/Default.html
Here's an technical preview of IE9.
Personal opinion:
Bad microsoft!!! Well... At least IE9 is better than Firefox 3.6. The only two arguments for me using Firefox3.6 are: OpenSource (or: not Google... ok, that's Sarcasm...) and the add-ons.
Chrome and Opera 10.5 are much quicker.
At least Microsoft got it - and it looks they do a quite good job.
Yours Michael
link seems to be dead?
Not for me...
no problem with the link and ie9 beta works fine here