Per a request for it, I’ve written up a WordPress plugin for adding in
a nofollow tag to links to any blog with a ‘wordpress.com’ within the
URL of the link. This was actually done for a WordPress Multiuser setup
that I host so that they wouldn’t get any link love. (Also because my
client doesn’t think much of wp.com)
Install it via the regular methods. If you’re running WordPress
Multiuser, I’d just drop it into the mu-plugins subdirectory.
Based on the Wikipedia nofollow plugin for WordPress
edit: I’ve gone ahead and removed this. It appears some folks out there, instead of seeing how and why this plugin was offered, would rather insult me over it. It’s not worth my time.