I've made a new layout called qwpr. It's slightly less ergonomically ideal than Colemak, but significantly even easier to learn (only 11 keys move from QWERTY, 9 of them on the same finger). It also has an accessible altgr¹ which gets you punctuation, arrow keys, and dead keys, thus making it significantly superior for programming and competitive with Colemak for languages with accents. You can see a feature comparison table and some Keyboard Layout Analyzer results including English, English with 5% backspace, coffeescript, and Spanish. The layout also has over 1000 (!) possible character outputs, including a lot of useful unicode symbols.

Since one of its primary advantages is an easy learning curve coming from QWERTY, I wouldn't expect anyone who's already made the leap to Colemak (or Dvorak) to switch. Once you've left QWERTY behind, any small advantages from switching are not worth the effort. Still, I thought people here might like to know.

It's currently available as an OSX .keylayout file and as a pkl layout.ini with images. I made a python script that converts .keylayout to layout.ini. The output is never perfect because of windows bugs, and so getting pkl to work (including workarounds for the alt-tab issue and some arrow key bugs) took some fiddling. Y'all are welcome to look at how I did it; just go to the sourceforge home page (first link) and click over to "files".

¹AltGr is on capslock; delete is on tab, and tab is on backquote and also in the altgr plane

So here it is (without the many dead key planes):