We have developed a plugin that helps users tag their travel related posts. It works as follows: you select some text and click a new button in the edit interface. In a popup you can specify exactly what you've written about: is it a story about the restaurant you've eaten in, is it a hotel review.
We (try to) use structured blogging and microformats to put the metadata back in the post.
When you insert you rss feed on Trayle.com, a map of your posts is automatically generated.
You can find it at: http://www.trayle.com/about/plugin
It's a beta (as is the whole web site) but we think the idea is cool. The next step will be to add a sidebar widget so you can feature the map of your posts on your blog too. Next week, I hope...
We appreciate any kind of feedback!