NVIDIA has not released any public beta Linux drivers for the 195.xx series yet, but they have released their first private beta to registered NVIDIA developers through their partners program. The two major changes that we have been made aware of with the 195.xx driver series for Linux is support for the yet-to-be-released CUDA version 3.0 and hardware support for Fermi.
We do not have much information on CUDA 3.0 at this time, but Fermi is NVIDIA's next-generation graphics processor that will be marketed as the NVIDIA GeForce 300 series. The first GeForce 300 graphics cards are expected to launch next month with this Fermi chip that contains nearly three billion transistors. The GeForce 300 graphics cards will be going up against AMD's recently launched Radeon HD 5000 series with DirectX 11.0 support, improved GPGPU performance, etc.
As Andy Ritger shared in our recent NVIDIA Linux interview, with greater than 90% of the driver's code-base being shared among all platforms, there should also be other changes carrying over from the Windows focus with the 195.xx series and provides Fermi and CUDA 3.0 support on the horizon too for FreeBSD and OpenSolaris.
We would expect the NVIDIA 195.xx Linux drivers will go into public beta once the GeForce 300 "Fermi" GPUs begin shipping in December, hopefully.