The Xfce 4.8pre2 release particularly focuses upon resolving bugs that were found during Xfce 4.8pre1, but there was some feature freeze exceptions made with new Xfce panel features for proper support for editing the application menu and integration support with Compiz view-port. The application menu editing can now be handled by GNOME's Alacarte.
The Xfce 4.8pre2 release also marks the beginning of the 4.8 string freeze leading up to the official release. The 16th of January is the expected date of the official 4.8.0 release of this alternative desktop environment to GNOME and KDE, among others.
The Xfce 4.8pre2 release announcement can be found at Xfce.org.