Boost release 1.59.0 beta 1 is now available from SourceForge
See http://sourceforge.net/projects/boost/files/boost/1.59.0.beta.1/
For details of what's in the release, see http://www.boost.org/users/history/version_1_59_0.html. 
Note that the links to files on this web page are for the final release - use the SourceForge link above to get the beta files.
Please download the beta, give it a try, and report any problems you encounter.