Just a quick post, nothing particularly spectacular but useful nonetheless. If you use the Multi Site functionality of WordPress 3.0 (and I expect this works for WordPress MU too), you might wonder how you can verify your additional blogs with Google, Yahoo and Bing given that each blog has no sub-domain folder to upload the verification files into.
There is an easy solution, install the header-footer plugin, activate it across your network of blogs then place each blog’s verification details as meta tags into the HTML header field (for all pages) provided by the plugin.