I also would like more information on the purpose of these. I'm using "All In One SEO" and and I'm extremely careful about everything SEO. I'm assuming that if these aren't used and the AIO SEO plugin is active, that they are ignored? I saw Juggledad's post here
http://forum.bytesforall.com/showthr...=custom+fields on how to add a hash before the entries in functions.php to disable them - is that necessary? For background info, I just upgraded my entire site to the latest WP and also ATA 3.53 yesterday. Thanks!