Carrier IQ. Here is what Apple has to say about it via All Things D.
We stopped supporting Carrier IQ with iOS 5 in most of our products and will remove it completely in a future software update. With any diagnostic data sent to Apple, customers must actively opt-in to share this information, and if they do, the data is sent in an anonymous and encrypted form and does not include any personal information. We never recorded keystrokes, messages or any other personal information for diagnostic data and have no plans to ever do so.
This is coming on the heels of a few manufacturers and Verizon publicly saying that they don't install or use it. Looks like the guilty parties will be revealed soon. In other words, who will be the last to publicly denounce Carrier IQ?