Today Microsoft announced the availability of the Windows 8 Release Preview (fancy name for Release Candidate) in 14 languages. The build is 8400. You can download it here.
In his Building Windows 8 blog, chief Steven Sinofsky says that this will be the final pre-release version available to the public before Release To Manufacturing/retail availability. He does not go into much detail about what’s changed in the Release Preview, although he does note that “Internet Explorer 10, new Windows 8 apps for connecting to Hotmail, SkyDrive, and Messenger (and many more), and hundreds of new and updated apps in the Windows Store” are included.
Source: Building Windows 8 blog.