Here's one: WordTube uses [media] while Media Tags uses [media-tags]. A clash between two plugins, even though the shortcodes are - to human eyes - different.

Now I know (from asking) that it's a WordPress issue, but it doesn't help!

A list of 'claimed' shortcodes would be good, but given the number of plugins that aren't tested as compatible with recent versions of WP, there's have to be a way of saying, for example, that any plugin not testedwith the latest version (or latest version minus a dot point or two) can be released for re-use. We're at 3.2.1; should anything not tested with version 3.x be removed, or highlighted in some way?

Gary