The driver version is 190.29 and can be downloaded from developer.nvidia.com.
In addition to the core 1.0 API, this driver supports a number of extensions, "which enable significant acceleration across many image processing disciplines". These extensions will be added to OpenTK in the near future.
Personally, I hope to start using OpenCL for signal processing and pattern matching, as soon as Ati releases GPU-accelerated drivers.
Are you planning to use OpenCL in the near future? If yes, for what kinds of projects?