I know this has been rather a painful wait for some people who have been anticipating great things from the 1.6.0 series. So I thought I'd just post to say that we are nearly there. I can only speak for the Windows release personally but I'm now about 90% sure that this will be out by the end of December.
If you simply can't wait any longer then you might like to sign up to our mailing list. Some pre-beta binaries are starting to circulate there for those who are willing to test the latest version of Mixxx and provide feedback.