I have been using Parallels 7 for some time now with Windows 7 64 bit. Lately I have noticed that many times typing in a comment box on a web page or a search box I either have missed key strokes or they do not register immediately. Most of the time they simply don't register. Now at first I wrote it off as just not pressing a key hard enough. But when I focussed on typing I realized that unless I typed real slow the key strokes were not being recorded all the time. Best that I can tell this is a IE 9 related thing and not sure if it would be related to the hardware grahpics rendering or what. Not every thing behaves this way. I am typing in this forum and key strokes are fine.
I noticed the same thing in Windows 8 32 bit in Parallels when typing in a Gmail message. Got annoyed and typed the message in Safari. Have been playing with Windows 8 all weekend, and only noticed the issue in Gmail. Have also noticed that when the Win 8 session is booting that I temporarily lose all input (keyboard and mouse) while the app is "thinking".