I had the same issue. Drove me crazy, Kernel panic with every viewer, and randomly. Seems the issue is the graphics switching. When MacBook goes to the Nvidia card it soon crashes. there is a fix that seems to be working for me which allows me to turn off the switching. gfxcardstatus, Stay with the integrated graphics, i know that sounds stupid but it keeps it from crashing. Hopefully apple will find a solution for this.
http://codykrieger.com/gfxCardStatus