Apple has addressed the random shutdown of some Macbooks with a firmware update.
http://www.apple.com/support/downloads/macbooksmcfirmwareupdate11.html
I guess there were 2 issues causing this. One, the software issue and another an issue of a thermal sensor wire too close to a heatsink which gives it false information making the computer shut down to protect itself from overheating.
http://www.apple.com/support/downloads/macbooksmcfirmwareupdate11.html
I guess there were 2 issues causing this. One, the software issue and another an issue of a thermal sensor wire too close to a heatsink which gives it false information making the computer shut down to protect itself from overheating.