Almost 10 days ago I switched my layout from QWERTY to Colemak and didn't look back.
My usual speed with QWERTY was about 65 WPM, but on a couple of times I got 75 WPM. I was never a typist/keyboard enthusiast, until mid september, when I decided I was going to learn Colemak and start touch-typing.
For a few days, I spent at least 1 hour everyday playing with this typing tutor for mac called Type-Fu. I did this for 10 days until october 5th, when I was already doing ~30 WPM with an average precision of 95%. That was my last day with QWERTY as my main layout.
I started playing some typing games (TypeRacer and 10FastFingers) in different periods of 1 hour or less several times a day.
Today, it was my 10th day on the cold turkey approach, and my average typing speed is already at 55 WPM, almost the same I used to got with QWERTY, and a few times today I even got ~60 WPM.
I'm pretty happy and excited because I have already almost the same speed I used to have with QWERTY, after only ~20 days. I'm still kinda slow with stuff like punctuation and uppercase letters, but hopefully it will get better on the next few days/weeks.
Here are some charts:
TypeRacer, until yesterday.
My last 50 tests on 10FastFingers, today.