I don't have 11, but in 08, when you change the zoom in a doc and then create another one, that zoom setting still applies. For example, I always create at 200%, and the only time that value changes is when someone sends me a doc at a different zoom. Maybe that's no longer the case with 11.
By the way, in 08, is there a way to lock the toolbar so I don't have to select Reviewing every time I open another doc? I could have sworn there was a way to do it, but now I can't find it. Anybody know?