When I use a certain program that gets always listed as the latest app in the alt+tab handler just before the desktop entry so when I hit alt+tab I get back to the desktop.
The program I'm noticing the issue with is HoneyView 5.08.
Link: http://www.bandisoft.com/honeyview/en/
How to reproduce:
Have a folder with some images inside (I have about 60-80 in the folders but probably even less is enough)
Right click on the folder to bring up the menu
Press V on the keyboard to start the program (at least V is the key shortcut I can use locally, not sure if it will change for you)
If you look at the ALT+TAB handler the honeyview window is listed as last just before the desktop one
I can reproduce the issue every time, I have also the app setup to open as fullscreen (just press F11 when you open it, close the app with ESC and next time it will open fullscreen by default).
I am noticing also the same issue with Media Player Classic x64 now.
I didn't have issues with either app on 7.0, infact I tried going back to the 7.0 version and I'm noticing any issue anymore with ALT+TAB. There is no mention of alt+tab changes in the beta changelog but it seems that something was indeed changed and is causing issues.