An article on Today discusses the rise in reported incidents of shattered glass cookware, including Pyrex cookware. The article cites data from the Consumer Product Safety Commission (CPSC). In one reported incident, a glass Pyrex pan containing a Christmas casserole literally exploded on the kitchen table. Some of the rise in shattered glass dishes could be due to hot cookware being set on today's cool granite countertops. It could also be because a different type of glass is used today and this glass is not as good as resisting quick changes in temperature.
Today reports that World Kitchen - the parent company of Pyrex - is disputing studies, such as this one from the American Ceramic Society Bulletin, that found the new glass used in its cookware shatters more easily than the original glassware. Take a look: