Typing is definitely a valuable job skill, when you have other skills to supplement it. You may not be able to be hired as a medical record transcriptionist without medical record knowledge, but you won't be hired as one without a good typing ability, either.

I found a fun site that gives you snippets and records your speed over time: Typing Test - Typing Test (Key Hero)

I get in the 90s with qwerty and in the 20s with colemak. I think I'll switch back to colemak for the rest of the night now!

I learned to type fast by playing trivia on IRC. I gave that all up and forced myself to learn homerow qwerty in middle school (god that's hard to spell when you aren't using it!) and gained at least 20 wpm. My best ever time was 145.

The hardest thing about learning another layout is that you are rendering yourself somewhat mute. I think slower so my hands can keep up, and I forget my train of thought by the time I get to it.