MSDN 1.0
Mihai Parparita: Blogs hosted on MSDN seem to have started to generate Atom 1.0 recently. However, perhaps due to a misreading of the Atom 1.0 spec, each entry contains a link node with the relation set to “self” when pointing to the HTML version of it (instead of "alternate").
Google Groups did this for a while too when it switched to Atom 1.0, so it seems to be a common error with developers that are just starting out with Atom generation. It would be nice if the validator could flag these errors.
It looks like there are two errors, both should be easily correctable. I’m confident that MSDN will address them quickly.