I just moved from a 2010 Macbook Air to one of the new 13" MBP and went to plug in my P2311H Dell Monitor only to find out it did not work! I previously used a MDP-HDMI Adapter with an HDMI-DVI cord to plug in the monitor with my macbook air no problem. Got my new MBP 13" only to find out it does not work at all. I tried another HDMI-DVI cord and still nothing. The MBP detects the monitor but displays nothing. Part of me wants to drop the extra dough and get a MDP-DVI adapter to use with just a regular DVI cord but I do not want to spend the extra money when this set up I had before should work fine. There are several posts on Apple's support forums about problems with Thunderbolt and DVI. What do i do?!?! Another note, on the new MBP, when I use the MDI to HDMI adapter with an HDMI to HDMI cord on my HDTV, it works just fine.