I'm still experiencing this issue. Killing iPoint.exe and re-loading it fixes the issue for me, at least for a while. I'm almost certain this is an Intellipoint driver issue.
It's not an iPoint bug. It's an Alt+tab bugg. Alt+tab is part of explorer so it's an explorer bug.
I didn't say it was an iPoint bug, I said it was an iPoint issue. If iPoint is hooking into the shell in such a way as to occasionally break the Z-Order of the windows during Alt-Tab, then the issue *is* with iPoint.
It's not about the shell being "fragile" or anything of the sort - anyone can write a bad Explorer plugin and have it break shell functionality. At the point that someone is writing something that interfaces directly with the shell it's the responsibility
of that developer to ensure it functions correctly. I can write a system level driver that blue-screens Windows, but contrary to popular belief this is not Microsoft's fault for making their OS "fragile", it would be mine for writing something that plays
with system-critical components and doesn't play nice.
Now, the fact that this "3rd party" mouse driver software happens to be written by Microsoft doesn't make the interface layer any different - it just makes it more embarrassing for Microsoft that they haven't fixed it after so long.