[Comment on Sam Ruby post RDF Tax, his comments choked]
I guess finishing the XSLT just landed back on my plate... @enIf the domain of your data is already covered by Atom, then pretty soon you won't even need to worry about the XSLT - just publish Atom and let GRDDL look after the conversion for the consumer on the fly (using the namespace as a key and treating Atom as a Custom RDF format).
There are a few Atom2RDF XSLTs in circulation, I'll check which is the most complete (at hand I've got these atom2turtle, atom2rdfxml - both half-baked).
re. Planet RDF - I've pinged Dave Beckett (the maintainer), there's a snag with multi-author blogs, see #swig chatlogs.
Now that you mention it, I may have some questions in the near future going the other way, getting Atom out of RDF systems (i.e. for a ConverterFromRdf)...