Atom versus RSS
David Heinemeier Hansson in the comments on one of his entries:
Joe: Atom is just RSS without the bugs. [...]
What he said.
The more I've learned about syndication formats, the more thankful I've been that I picked Atom way back when. (I'm not sure why I chose Atom; possibly because it seemed the more up to date of the choices at the time, since it had an RFC in development and all.)
The difference between Atom and RSS is that Atom has a real specification, one good enough that people actually write to it. So I can use the specification to write a useful feed generator, which is pretty much what I did for DWiki (with some help from the feed validator).
With RSS, the formal spec is unclear and incomplete, so in practice RSS is defined by what popular feeds and feed readers do. This had led to various problems and dark corners, where sometimes nothing you can do is going to work for everyone. (I'll stop footnoting that now; I could go on all day.)
In my opinion, voodoo programming is no way to run a railroad. So I am really glad I went with Atom; I would probably have found dealing with all of the RSS issues to be teeth-grindingly frustrating.