I haven't measured it in a long time. When I was in middle school, I took a keyboarding test, and I think my speed was around 60 words per minute. I could be a little faster or slower than that now... not sure.
However, one of the key things is the ability to copy/paste/edit quickly.
SPEED EDITING TIP: Hold down the "shift" key on the keyboard and use the arrow keys to highlight text (without having to take your hands off the keyboard -- the mouse just slows you down!). Then you can control+X, control+C, and control+V to cut, copy, and paste.