I did some research on Pyrex a little while back - I'll paraphrase what is still in my memory, so there could be some slight flaws to it, fyi.
It seems that this is a much more common occurence for newer pyrex i.e. pyrex bought in the last 10 yrs. As many of us know who've inherited Pyrex from our mothers or grandmothers, those suckers take a licking and keep on ticking. However, apparently Pyrex was bought by another corporation. It seems that since then, there have been alot more incidences of not just breaking, but exploding (as some of you have written.) Yes, some can be excused by things like temp changes (Adding liquid, etc), and they do tell you to NOT put Pyrex on a stovetop to let it cool. But for some people, it was just a matter of pulling the darn thing out of the oven into the ambient air and having it go off in their hands, or having it go off in the oven. I read a number of these stories on consumeraffairs.com.
My point is that regardless of the "reasons," some of which seem to be no error on the side of the chef, these things just seem to be alot more dangerous than they used to be. I still have some older Pyrex, but I won't buy any new. Not after the stories I read.