XRSS namespace proposal I made earlier this week.
The others are a new specification for the Really Simple Syndication format and a best practices profile, a set of recommendations for how RSS documents can work in the widest possible audience of aggregators, browsers and other software. I published the first draft of the profile this morning, which will be filled out one section at a time.
We could use more participants on the mailing list to work on the profile. A "best practices" document has a much better chance of being true to its name if a bunch of RSS publishers and developers contribute to it.