Found this over on Neowin.net:
Microsoft has quietly released the latest test version of Internet Explorer 7.
The RC1 build includes improvements in performance, stability, security, and application compatibility. With this build, Microsoft has also made enhancements to the fit and finish of the user interface, completed CSS platform changes, added language support and included an auto-uninstall feature in Setup, which automatically uninstalls prior betas of IE7 making installing the new build even easier.
IE7 RC1 is available in English today, and all localized versions of RC1 will be available in September including Arabic, Finnish, German, and Japanese as well as the French and Spanish versions which will be available for the first time.
Microsoft is expected to finalise Internet Explorer 7 at the same time as Windows Vista.
I’ve been running the Beta 3 at work for sometime…time to update it! RC1 holds the build number 7.0.5700.6CO.