Do you use Posterous to update your site? I prefer to use Yahoo and Gmail to update the site rather than thru the Posterous site. Why? It’s easier to add images. You can add tags to your posts when you blog by email. Here’s how.
How to add tags to Posterous blog posts
1. Click in the subject of your email
2. Use the syntax ((tag: Startup, Business Plan, Template, Whatever)).
Your tags will be displayed when you post.
You can also go in and change the tags on the Posterous site.
More tips over here: http://ivanwalsh.posterous.com/