I haven't diddled around Azeroth in a while, but let's just say I know my way around a 25-man. And Mad Catz's new Cyborg M.M.O.7. gaming mouse looks like it's good enough to play at a pretty elite level.
The Cyborg M.M.O.7. is the not-so-distant cousin of the Cyborg R.A.T.7. Albino mouse, but it's got some useful MMO-specific features. It has a total of 78 definable commands via 13 programmable buttons, a 2-position shift button, a cycling MMO Mode Switch that cycles through three separate button sets—think different stances, specs, or the equivalent—and a "lock" feature that will allow you to toggle the right or left mouse button perma-clicked for long virtual commutes. It's also got a custom World of Warcraft addon that lets you drag and drop from your spellbook, and has profiles for the top MMOs that are pre-programmed with typical setups for those games.