The release announcement for FreeBSD 9.0 Beta 2 is very brief but to the point:
7 September: The second BETA build for the FreeBSD-9.0 release cycle is now available. ISO images for the architectures amd64, i386, powerpc, powerpc64, and sparc64 are available on most of our FreeBSD mirror sites. One of the many new features in 9.0 we would like to be tested is the new installer, so we encourage our users to do fresh installation on test systems.
There's also more information about FreeBSD 9.0 Beta 2 on the project's mailing list.
Compared to the original schedule from the FreeBSD Wiki from release engineering, the current beta 2 is more than one month late (originally scheduled for 3 August). The final release of FreeBSD 9.0 was originally anticipated for release today, 7 September, but will likely not make it out until October based upon the ongoing development delays.
For those interested in learning more about the features of FreeBSD 9.0, see the FreeBSD-CURRENT release notes.