I'm running quite a few portable apps in Windows 7 (7260 build from the vhd), Photoshop CS4 runs fine for me. Though other apps require me to run them as administrator in order for them to work (ConvertXtoDVD is the main one, I love that program). Photoshop runs both normally, and as administrator absolutely fine, I have it pinned to the taskbar as well, and that works just as well.