So a great new feature in Lion is you can have a mini hooked up to your HDTV viewing one account for watching movies and can also remote login under another account to do other work-like things. Unfortunately when set up like this when you play videos on the HDTV they are choppy, e.g. 720p x264 movies played in VLC. If you log out of the 2nd virtual display then the choppiness disappears. The CPU usage is low, 8GB memory and lots free, the disk read speed is fine and I increased the VLC file buffer. So a possible conclusion is that the Intel GMA 3000 doesn't have the power to drive 2 displays (even 1 only being virtual) and show 720p x264. I was wondering if anyone with the 2.5Ghz with the discrete Radeon could try this out and see if maybe the issue is something else.