There’s a great discussion on the Extreme Programming Yahoo! group where a whole bunch of folks list their blogs out. If you aren’t part of the group, you should probably join it (it focuses on technical practices, and there’s lots of other good agile stuff there too). The discussion starts with a message from James Carr where he asks who else here blogs?
It’s probably still cool to jump in with your own blog link if you have an agile-focused blog (I’m sure Scrum, Lean and other agile methods would be welcome even though it’s an extreme programming list!)