Benjamin and I we’re working on Geolocation support for Flux CMS resp. its blog plugin last week.
You can now either use Plazes for automatically geoannotate your blog posts (like this one) or you can use the tagging system for places where Plazes is not suitable, like if you are on a mobile network. As you can now also tag your posts via mail/mms, you can copy&paste your longitude/latitude data from a gps device into your posts and then the blogpost is automatically annotated. Also in the RSS feed, of course.
More about the Plazes support can be read in this devblog post, and more about the moblogging part in that devblog post.