Dear Tim,
Regression testing. Spend the money on it.
At the company I work at, we do tests on edge to LTE data on AT&T and Verizon (Sprint is also coming soon). The programmers work hand in hand with the testers to create as many scenarios as possible. We even go to client sites and test new releases. The end client has to be 100% happy.
This is not the only repeat major security bug in iOS 6.1! I found one last night. You can use universal search to find iMessages that have been deleted!
I was shocked when I found it. I have reported the issue to all the tech sites. I hope one of them will publish it so Apple fixes the issue!!!