I recommend the following 2 steps program:
Stop sending your url
If you already have used WordPress 2.3, use the 123 Anonymer Versionscheck 0.10. It will anonymize your data, but a minimum of 1 request with personal data will happen, that is while using the plugin page.
If you do a fresh install of WordPress 2.3, i’d go with the my-hacks.php solution, because that way, no personal info will be send.
Lots of unnecessary Akismet informations
After finding the update problem this morning at Lumières dans la nuit, i read the following group. To my surprise i’ve learned, that the Akismet Spamchecker sends all of the $_SERVER environment variables from your server to the Akismet server. W T F?? I myself use Akismet in a custom project, there is absolutely no need to send this information. To stop sending this information, open akismet.php in your favorite editor, search and remove the following lines:
foreach ( $_SERVER as $key => $value ) if ( !in_array( $key, $ignore ) ) $comment["$key"] = $value;