Sorry for not updating the threads on this. We have gotten the crash logs from apple and are classifying/investigating them. In regards to the sign in crash bug it seems that there are a small percentage of users that hit one of a few different, but related, issues causing the crash. We're working on some fixes now and we'll be testing them soon. I'll post back once we have a better idea for a release date, but it should be relatively soon.
Keep the faith, we're working on it.