The NVIDIA 319.12 Beta for Linux introduced support for Optimus-like functionality, initial support for RandR 1.4, improved EFI support, new hardware support, performance fixes, and a whole lot of other work.
The NVIDIA 319.17 Certified driver was now released this morning with more changes. First up, the new hardware support for this driver is adding in the GeForce GTX 650 Ti BOOST, GT 720M, GT 735M, GT 740M, GT 745M, and GT 750M.
The 319.17 driver also has in various bug-fixes, updates to NVIDIA Settings, a security fix, a nvidia-persistenced daemon for improving the driver's start-up time, and a ton of other features.
The full list of the extensive changes to be found out of the NVIDIA 319.17 Linux x86/x86_64 graphics driver can be found on the NVIDIA.com release page.