SDF
Here's someone who was fed up enough with the RSS/Atom format war that he created his own syndication spec: SDF (Streaming Document Format). I admire his moxie, and the spec is a good example of a readable specification document.
Potential adoptors (publishers, consumers, and everyone in between) are going to look at the cost/benefit for supporting yet another format. Are the benefits compelling enough? At first glance, I'd have to say no, but I won't dismiss it out of hand. It's something to keep an eye on, but it's got a loooong road ahead of it.
If the effort does start to pick up steam, it would be easy enough to extend FeedBurner's SmartFeed service to make SDF feeds work with legacy readers.
Source: An Appeal to Unity: The Driving Philosophy Behind SDF - howdev.com