Today I spent some time on implementing the Atom 1.0 specification for my next version of KillerBlog. My blog-engine uses typed DataSets. All syndications are created by performing an XSLT transform on the XML data representation of a SyndicationDataSet. This makes it really convenient to implement additional formats, because it is just a matter of shifting some elements within the <xsl:template> structures.
The older Atom 0.3 format is considered deprecated, and the Atom and RSS Feed Validator will not approve your feeds anymore. So, if you feel like implementing Atom 1.0 as well, you should check out the AtomEnabled website, and especially the developers section.
There turn out to be two libraries for .NET around:
Just in case to need to create the Atom feed programmatically from an object model.
I’ve also slipt/hotfixed the new feed in place of the existing 0.3 one on the current KillerBlog version. If you subscribed to any KillerBlog old Atom feed, place update your links. The Valid Atom link at the bottom is removed, till I get a chance to upload the new release.