…and yet I can’t use it (on ubuntu 10.10). I’m frustrated, I really want to get my hands on this yet it is very elusive, I feel as though windoze users have a better go at running a linux app. Krita looks like a really cool program, it just takes a computer scientist to run it, which is a shame. Blender is the ultimate role model of how programs should behave. Just ranting here. Hopefully ubuntu 12.04 will have krita 2.4 in the repos 
I just tried Windows version from http://www.kogmbh.com/download.html.
It really is impressive. It the only CMYK raster image editor that is free and open-source.
New unstable Windows build at http://www.kogmbh.com/download.html
… and news about what’s going to be in v2.5: http://krita.org/item/111-looking-forward-to-krita-25