Release 1.49 of the Boost C++ Libraries is now available, yuppie!
Have a look at the specific release page on boost.org for details.
Download the zipped package from sourceforge.net.
I am currently in the process of generating the lib and dll for my (Windows) development environment, I had a yyacc error message (not such file) in the bootstrap phase, but I guess it is not an issue, b2 is running fine. If you don't get what I am talking about, you should probably have a look at the Boost Getting Started, or to my post written where I installed the beta version of this same Boost version.