from diveintomark.org: The myth of RSS compatibility:
There are 9 versions of RSS, all of which are incompatible with various other versions. RSS 0.90 is incompatible with Netscape’s RSS 0.91, Netscape’s RSS 0.91 is incompatible with Userland’s RSS 0.91, Netscape’s RSS 0.91 is incompatible with RSS 1.0, Userland’s RSS 0.91 is incompatible with RSS 0.92, RSS 0.92 is incompatible with RSS 0.93, RSS 0.93 is incompatible with RSS 0.94, RSS 0.94 is incompatible with RSS 2.0, and RSS 2.0 is incompatible with itself.
