Also, the new iOS notification system on iOS 4/5 was directly nabbed from a jailbreak tweak, though it was because they hired the developer so I am assuming it was not "copied" in that case.

Similarly, with Notification Center I've never previously heard that credited to the jailbreak community because it was always mentioned as an area where iOS caught up to Android, which also seems likely as the inspiration for a jailbreak as well.

Customers saying "I really want X" is generally just empty words with poor correlation about how much X is wanted, and you should take that with a grain of salt instead of assume that there's a demand for X; but on the other hand if there's a price attached (either a literal payment, or price of inconvenience as in this case) then seeing if customers really want this is very useful data.