What cracked screen problem?
Like earlier posters I have had my Nexus 7 for awhile as have many of my friends and no reports of cracked screens. One friend did have the screen lift problem.
On the other hand I have some co-workers who have dropped their iPhones and cracked the screen. Does that mean there is a cracked screen problem with iPhones?
Any device with a glass screen is susceptible to cracking the screen if dropped or hit. It is just a characteristic of glass.