Now this has also happened to me, although it seems to have happened in two parts. First I opened my phone to see some sort of Sprint updater message, and Lookout as well as a few Sprint apps were installed. I uninstalled them, and went to sleep. When I woke up they were reinstalled and my home screen was rearranged and there was also a new Sprint Discovery widget.
I saw this thread last night, before it happened, or I probably would have freaked the F out.
Just to be clear - What process is doing this as I would like to disable it? Is it the Sprint Installer, or the Sprint ID? Do we even know for sure? It's wicked annoying. Auto installing apps is one thing, but they should not have the ability to change my home screen setup.
If at first you don't succeed, skydiving is not for you.