I've published a new draft of OCS version 0.5.
Based on the poll I did earlier this year I have tidied up the RDF to make it more similar to the RSS 1.0 style (and made it valid RDF at that!). Schedules and formats can be shared between channels and I'm planning to provide a standard set of them. The spec also allows extension modules to be created for OCS, a sample one is the Alias Module that allows alternative (usually defunct) urls to be supplied for channels.
As usual, discussion of the draft should occur on the Syndication list.