Charlie Calvert, C# Community program manager announced the availability of the second Release Candidate of IronRuby. “As IronRuby approaches the final 1.0, these RCs will contain crucial bug fixes and enhancements that IronRuby requires to be a fast and compatible 1.0. Now that IronRuby is in the release-candidate stage, your feedback is even more important. Please use these new binaries as much as you can and report any issues you find.” The actual version of the assemblies is "0.9.4.0"; they will be updated to "22.214.171.124" when the last anticipated RC of IronRuby 1.0 is released.
Download: IronRuby 1.0 Release Candidate 2