I just got one the Matrox MXO boxes. It is a nice way to directly get HD-SDI out of your Mac... So I wonder if this would be tool to be used with Catalyst.
Not that I had an actual project for this in the pipeline - but quite often the first thing behind the Media server is a Folsom Image Pro that does nothing else than decoding the DVI / VGA signal and encoding it in Serial Digital...
And when you compare the prices of the Image Pros and the MXOs - I might think it is worth looking into it...