There’s a new test build of Internet Explorer 7 ready to roll. Microsoft is making available to any interested parties on August 24 the Release Candidate (RC) 1 IE 7 bits for download.
There’s a chance this is going to be the last public test build of IE before Microsoft releases the final product in the fourth quarter of this year. New in this build: Performance, stability and CSS tweaks.
I have been using it and for me all seems fine and it works well. It takes a while to install but it will uninstall the previous version of IE7 for you and do a few reboots then it is ready. For me it is better than Firefox.