The problem as I see is that often users (like my mom) will experience great grief as they mash their keyboards frantically - enabling their caps lock without really noticing. Whereas users who know how to use the thing often don't because, WHO THE HELL TALKS LIKE THIS?
I suggest a GREAT solution! Re-purpose the "caps lock" key for something useful and assign "keyboard gestures" to keys.. I suggest that one of the shift keys be altered, to, by convention, upon being "double clicked" (or maybe triple or held for a long time, etc), it will enable a caps-lock, and the effect "fades off" after inactivity. Have an LED continue to indicate the state of the "key".
I provide this idea free for all to use and implement. So, Microsoft, Apple or whomever that wants to retro-actively patent this idea, can SHOVE IT for trying to continue to abuse the nature of the patent system. This is a free, open idea. That said, it would be nice to get verbal credit or something. But really, just do this (and variants for other barely-used keys) and let's move on!