This shouldn't be much of a surprise. There have been reports of random MacBook shutdowns for months, and Apple even copped to the problem last month, but there's not been much movement since then.
I didn't sign up at either of the petitioning sites, but I could have. I bought my fiancee a MacBook about a month after they were released and within a week it was shutting down at will. We were lucky, though. We made an appointment at Apple's main store in London and after the Genius witnessed two shutdowns in as many minutes, he said he'd give us a brand new MacBook. Things have been OK so far.
Are any of you still suffering with the same problem? How has Apple handled your complaints? Sound off in comments.