How can programming skills be categorized?

I'm currently working on a side-project, a CV creator if you will, targeting IT professionals (and engineers, but that doesn't really apply here). Currently, I would like to have a database of most common skills of each areas of programming (because users can enter their own as well), to ease the burden of my users.

So far, here's what I got: Programmer Skill Lists Note that while Web Development is mostly finished, everything else is still a big Work-in-process, and I would love your input. Thank you!