No, the web site is not updated yet as I write this, but the announce has been sent out to the subscribers of the freebsd-announce mailing list and all the files and ISOs are into place for immediate download. You can read it at BSDForums.org. One of the most significant changes in FreeBSD 4.6 is the adoption of XFree86 4.2.0 as the default version of the X11 System. Some contributed programs have been updated, such as sendmail and the ISC DHCP client. For more information about the most significant changes with this release of FreeBSD, please see the release notes.