Which SDK to use for OpenCL programming


I’d like to know which SDK is best to use for OpenCL developement. In early 2011, there has been an OpenCL-SDK in the developer download section, but I haven’t heard about an updated version of that. Regarding the CUDA SDK, I did not read anything new on OpenCL in the release notes.
So, is there a recommondation of NVIDIA what to use?

Thanks for any hints

Thanks for the reply, Wanderine!
However, on that site I can’t really find an answer to my question given above.

Does anyone else know, if and if yes, how the OpenCL support differs in the different CUDA SDKs?