In reply to Alec.

I understand the security reasons point, but shouldn't that policy also not allow orphaned tables (of inactive/uninstalled plugins) on your live sites? Why would it not allow files of an inactive plugin, but it would allow data of an inactive plugin?

I also recognize why Jeff was happy that the data of a deleted plugin was still available, but I consider that a lucky accident. The fact that the data was still there undid his mistake of deleting the plugin, but I believe that most of the time, deleting a plugin is not a mistake. I think the data shouldn't be kept just in case the plugin removal is not actually what the user intended, or made it final.

I do agree with presenting the user with the option to keep a plugin's data (import/export), but it would probably a little too advanced for the average user.

Another thought: have a "Trash Can" for old plugin's settings. Just like deleted Posts and Pages have their separate space from which you can restore them, maybe a part of the database where all the "trash data" goes could be helpful. It could be restored when needed, but it would be in a separate part of the database.