They've removed the required stable identifier (rdf:about) from the entries, which was the main thing RSS 1.0 had going for it.
Brent and Dare have already raised this, and it's being considered as a bug and dealt with. See the following for further details:
http://lists.xml.org/archives/xml-dev/200501/msg00421.html
Thanks,
-- Sean B. Palmer, http://inamidst.com/sbp/
