Many modern blog platforms (most of them actually) let you publish data by email. You can just send email to some service address and platform transforms it into a new post. For example, in Posterous you can send data to post@your_blog.posterours.com, in Friendfeed it is firstname.lastname@example.org, in Blogger you can set address in Settings->Email&Mobile tab etc.
A new mashup Geo posts lets you create a personalized mobile web application for posting geo related data to your blog. Just set a service email address in the form below and get a link to mobile web application for iPhone, Android or S60 platform. This web application lets you email new postings right from the map - just click on the draggable marker presents the location. And application automatically adds to email a link to the location. So your posts will have a direct link to some map. It is probably the easiest way for sharing locations, write about some check-ins, lets your readers to see the place you are writing about etc.