I have this issue when debugging mobile apps on the emulator. When I press F5, the build starts, then the deploy, then the app pops up in the emulator. Because this takes a minute or 2, I am checking my SO score and maybe ask a question while I wait, and the emulator is in the background. When I finally switch back to the emulator, it shows the start page, not my app.
I figured out that by pressing the back button I can bring the debugged application to the foreground, but still, I don’t know what is pushing it into the background to begin with. Has anybody noticed this, and found a way to prevent it?
The default behavior in WinMo is that if the device has no activity for a certain period of time (set in Settings->Today->Items->Today Timeout), the Today screen will come to the fore. Check to see if that’s what’s happening (though I think the smallest interval is still larger than a couple minutes).