I've heard it's a little harder for people who have used physical keyboards to adjust, but not impossible. I can't provide any direct tips on the transition since I went from T9 (and rarely typed) to the iPhone keyboard. I will say one key thing though is learning to use autocorrect. Don't try and hit every key exactly every time when typing normal english, just go at a comfortable pace and let autocorrect catch the minor mistakes. Make sure you know how to correct the autocorrect system, so it can be tailored to you as you also train with it.

You also have the option on Android to try out a few other keyboards. Initially I'd say stay with stock, just to get a feel for it for URL entry and other non english pieces. Then once your fingers get used to the spacing, you can look at Swype for english text entry. In my short time with the Android phone last summer, Swype was something that did grow on me a bit after trying it out.