There is a problem with this.. I'm finding that the phone isn't always cleanly unmounting the internal & external SD storage so quite often it's corrupting app data for any applications you have on these. Anything that is installed to android_secure is placed on the sd.
This isn't normal. If you connect with USB storage then you should be given a prompt about running apps may be terminated and it should also cleanly unmount the drives. It looks like the phone is performing a force-unmount which is causing corruption.
So has anyone else had this same problem? Anyone notice downloaded apps disappearing?
Whenever I get root I'll have to dig into this and try and find a solution. The whole way the device manages internal and external SD is wrong IMO.