It seems a random app crash bug plaguing the iPhone 2.0 software has concerned El Jobso enough to make him personally reply to a user email. According to AppleInsider one of their readers received an email from Jobs that read "this is a known iPhone bug that is being fixed in the next software update in September."
AppleInsider says the app crash bug affects newly downloaded and updated apps, where they instantly quit upon launch. Sometimes reinstalling them helps, sometimes it doesn't. While the 2.0.1 and 2.0.2 updates have done nothing to remedy the problem, some speculate that the problem revolves around root permissions. Either way, this is the first Apple acknowledgment of the problem. [Apple Insider]