Boost release 1.40.1 beta 1 is available from SourceForge:
http://sourceforge.net/projects/boost/files/
This release contains one new libraries and numerous bug fixes for existing libraries. For details, see http://beta.boost.org/users/news/version_1_41_0 for details.
To install the beta on your system, see http://beta.boost.org/doc/libs/1_40_0/more/getting_started/index.html
Please report any problems with the beta on the developers or users mailing list.
Unless unexpected problems arise, the plan is to ship the final 1.40.0 release in a week to ten days.
Thanks,
--The Boost release team