[mharvey]

It seems that rotation is controlled by the position of the keyboard and not the accelerometer for most of the apps (like the Today screen, Text Messaging, Notes, etc). There are only a few apps that seem to use the accelerometer (Opera, Sprint TV, photo viewer). Even then the accelerometer is overridden by the keyboard if you open it. If the keyboard is open the application should switch to landscape mode, no matter what position you hold the phone.

In my case the screen would flip endlessly when the keyboard was open. I could also see the keyboard backlight flipping on and off as the mode was flipping. I believe that the fault was a bad switch or position sensor in the keyboard. The Touch Pro that did this went back to Best Buy and I have not had the problem at all with the new one.