This is basically an AdminCP tool that will list tables, with the IPB prefix only, that are not default tables of IPB or have been changed/modified (the structure doesnt match up exactly with the current version you're running). So under each default table if there was an extra column in the table that IPB wouldnt normally have (for that version) or a default column was different (different datatype or different length, or different default value, index, etc..) that table and column(s) would be listed.
This would be a useful feature because if you have done any modifications you can easily track down changes to your database. Either as a reminder, or a helper to revert these changes. If you choose to revert a selected change, it gives you an "ARE YOU SURE?" message.