It's one the most critical parts of user's experience and certainly this is not a place where we'll just write code and ship without testing.

The problem is that it didn't happen for all transactions and appeared to work for some users but not for other. Sometimes it worked for some user on one machine but not on another.

And another developer who hit it with his app in testing didn't understand it was Apple's issue. He created another test-user Apple ID and it worked then so he supposed it was kind of a glitch related to his use of the previous test Apple ID. Really, the last thing you'd think is that Apple has bugs in the payment system.