I've just installed sharedb on a site with 7500+ blogs on 16Dbs. Installation went perfectly fine, and all seemed OK at first, right after uploading db.php.
However there seems to be an issue with some pages, it seems on blog 1 only (which is in a separate DB - xxx_home0), most pages/posts are not being displayed at all in the site, some pages are giving a 404 and posts are just not showing up (empty). Also, the posts section and the pages section in the admin panel is completely empty after the migration (which is not supposed to be so), although they do exist in the database (i believe i've stumbled across them in the home db). I am also using WPML Multilanguage - if it helps.
I downloaded the installation ebook of Ron/Andrea, and followed every phrase, however i could not get it to work.
The plugin works fantastically as the whole site is much more responsive, however this issue with pages/posts not being available in the site admin is killing me!