atom (both the feed format and the publishing protocol) is excellent. it's well-specified, flexible, extensible, RESTful, and with appropriate extensions could be used to provide programmatic access to more or less everything that currently has an api. atompub is useful for more than just posting entries -- there is a standards-track feed history extension that, if implemented, would make it easy to write journal backup tools, and imho atompub could be a good replacement for the fotobilder protocol if dw ever provides a photo-hosting service.