Since MODs are being replaced by Extensions in the ACP, we should rename the .MODs tab. A suggested replacement was "Extensions".

http://area51.phpbb.com/phpBB/viewtopic.php?f=81&t=44021

Although instead of just renaming the existing ACP_CAT_DOT_MODS lang var, perhaps add a new module category and lang var: ACP_CAT_EXTENSIONS. This way, existing MODs held over from a 3.0-x to 3.1-x upgrade would maintain backwards compatability (and they would still be "MODs") and new Extensions authored for 3.1 should make use of the new ACP_CAT_EXTENSIONS module.