I've gone the entire week now using my new keyboard. My old mac one is sat in the corner and I haven't touched it. I went a couple of weeks of using both and before I knew it I was switched over. A few days ago I was just rattling off some text and my fingers were just flying.
I do find it hard for some of the shortcuts I used to use alot. For example the Subversion Textmate one is ctrl-shift-a, which is much harder on this keyboard. But a bit of time to change those and I'll be ok. I've typed quite a lot this week and the pain is way lower.
Special thanks to Andrew Burkhalter who recommended this too me.
One interesting note, I hate that Mac keyboard. Just hate it. I tried the other day and it's like typing into putty. I have to exert so much pressure on the keys which are soggy and horrid. No wonder my fingers were getting worse. Really I just want to do this to the damn thing: