After installing the Blog for Umbraco 4 package by Tim Geyssens, I noticed that the links generated in the tags menu were simply using query parameters instead of friendly URLs. I would prefer them to look like this: /blog/tag/tagname.aspx.

The good news is that Umbraco already uses UrlRewritingNet.UrlRewrite to create friendly URLs, so everything we need to get this working is already in place. After brushing up a bit on regular expressions I came up with the following two step solution.