As expected, the first Internet Explorer 8 release candidate became available for download this afternoon. According to a post on the official IEBlog, the RC1 build improves upon last year's beta 2 release in a number of ways:
Platform Complete. The technical community should expect the final IE8 release to behave as the Release Candidate does. The IE8 product is effectively complete and done. We'll post separately about the thousands of additional test cases we're contributing to the W3C. We've listened very carefully to feedback from the betas. With the Release Candidate, we're listening carefully for critical issues. Reliability, Performance, and Compatibility improvements. We've studied the telemetry feedback about the browser's underlying quality and addressed many issues. Security. We've worked closely with people in the security community to enable consumer-ready clickjacking protection. Sites can now protect themselves and their users from clickjacking attacks "out of the box," without impacting compatibility or requiring browser add-ons. We also made some changes to InPrivate based on feedback from customers and partners.
Some changes prompted by user feedback have also made it into this build. Microsoft cites the example of the favorites bar, where users should now have an easier time fitting additional items.
You can grab the release candidate from Microsoft's Windows Internet Explorer 8 page. Step-by-step upgrade instructions are available in this separate blog post, too. Windows releases from XP through Server 2008 are supported, but folks running the Windows 7 beta will apparently have to bide their time: "Windows 7 users will get an updated IE8 with the next update of Windows 7," the first blog post says. (Thanks to TR reader Ben for the tip.)