This project looks well thought out. I tried out 1.0rc3 of typeingteacher, 1.0rc2 of touchtyper.
Both had build problems for which I opened bugs reports.
The program was nice to use, but kept segfaulting (after a minute or so of use each time). Also reported this bug.
When these problems are fixed, I think it will be a good tool. I plan on having my sons use it even in the current state.
I've been trying to make myself trudge through "UML In a Nutshell" The book isn't bad, it's just too dry for me. I've learned more about UML and even new stuff about OOA&D going through the tutorial for ArgoUML than in all my other reading combined.
The tool seems to work very well, the price is right :), and it's extensible. I'd been planning on spending some serious budget dollars on Rational tools or the like, but I think I'll just run with ArgoUML :)