Dave is making another effort to pull RSS and Atom together with an outline of a proposal that differs from past attempts including mine (see Making Atom Happen and Atom-Syntax Sin Tax).  These are the bulletpoints of his proposal:

1. The format would differ from RSS 2.0 as little as possible.

2. It would have the great spec that the Atom people are promising. A great validator, and lots of support from developers who evangelize the format. There wouldn't be many flames because everyone would be getting most of what they want.

3. It would be managed by an IETF working group that would be open to anyone who wants to participate, not just me, or Sam Ruby or Blogger and Movable Type, but anyone who wants to make the effort to contribute to furthering the art of syndication technology.

4. It would be backward compatible with RSS 2.0, so that any 2.0 feed could become an RSS/Atom feed by changing (fill in the blank, as little change as possible).

5. The top level item in the feed would be called rssAtom. It's a problem for at least one aggregator that the top level item in Atom is called "feed" — not such a problem today, but later when another format comes along that also calls its top level item "feed." Formats in general should use a distinctive name for their top-level element. (Prior art: HTML, RSS, SOAP, RDF.)

In essence, he is suggesting a common format that is backward compatible with RSS 2.0 at the data model level instead of the syntax level.  I like the proposal and sincerely hope it works out, but engineers are notoriously bad at finding the reverse gear…