Sean Gallagher (of eWeek) describes the recent developments in synidcation standards saga in his blog. The article is a nice summary of where the RSS vs Atom story is now and a little about its history. There's lots of links to other interesting content. Regarding Atom, Sean says:

Atom combines a weblog publishing API together with a syndication format. Winer says that's not novel--"We did that with the MetaWeblog API," he says, which was based on RSS. "The clever thing they did was that they gave them both the same name."

But Atom is incompatible with the RSS standard, for a number of reasons, some of which I'll grossly oversimplify here. For one, it creates a new XML data format for syndicated content to allow for more data types to be built into an Atom feed. The publishing API is being brought into alignment with other web development APIs and approaches such as SOAP and REST, says Bray. And Atom will link into enterprise security models like WS-Security, through WSSE.

From RSS, Atom, And The Syndication Standards Dance
Referenced Tue Jun 08 2004 15:37:26 GMT-0600

Atom is working its way through the IETF process. Probably as a foil, Dave Winer has suggested that W3C may want to standardize RSS 2.0. There's one side to this argument that goes "it doesn't matter to the users as long as the aggregator writers support both." However, I think it does matter in terms of divided focus and energy. I'm not taking sides; I'm just wishing that the fracture didn't exist.