qUserKey updated for Mists of Pandaria. The original author (quel) has not updated this addon in nearly 2 years. I have attempted to contact him about updating his project, but have not yet received a response.
Begining with The Burning Crusade, the user interface may bind keys directly to spells, abilities, macros and usable inventory items; however, the game does not provide a gui for making such key assignments. UserKey scans you spellbook, your macros, your inventory (including your bank) and provides a gui for assigning keys to those actions/items.
UserKey adds a new entry to the main game menu called "User Key Bindings" directly below the original "Key Bindings" button. Click the button and scroll through the available items. Items from the spellbook are displayed first (with tabs/schools indicated), then macros, then usable items. Then click the item you want to bind, press the key you want (including CTRL, ALT, and/or SHFT) just like the official Key Binding interface.
If you wish to know what has changed:
1) Updated TOC to 50001
2) Changed loop (old code, line 901) to loop through the new spellbooks properly. (new code, line 897)
3) Changed references to UIPanelButtonTemplate2 to UIPanelButtonTemplate. (Blizzard removed the 2 version, and made the no number version the same as the old 2)