The patch that was committed to the X Server mainline branch and will find its way into X Server 1.7 can be found here. There really isn't too much to say besides that there is new VT switching support for OpenSolaris / Solaris. Certainly not as exciting as seeing Multi-Pointer X or a new acceleration architecture, but hey, it's there.
Right before this improved VT support was added, X Server support for Sun releases prior to Solaris 8 was dropped. If you want to update your X Server for your operating system that is more than ten years old, you will want X Server 1.6 or something older.