I really hope this bitcode feature isn't going to cause a lot of trouble for app developers. Up until now, the app you built on your machine (and tested on your devices) is the app you submitted and which is running on your customers machines.

In the future, when your app crashes on customer's machines and doesn't on yours, how are you going to debug much less explain this to apple and have them fix the issue for you?

This is especially scary when you consider the turnaround time of ~2 weeks before your new build becomes available in the app store for you to test.