Apple has zero restrictions about open source code running on iPhone - the poster is incorrect. Also, music sharing is entirely possible, just don't expect it to be supported as part of the first-party pipeline... the dev license itself doesn't prevent you (unless your purpose is to illegally share).
"Remotely disable your apps and media" — did that happen to anyone?
Users who downloaded applications which Apple later pulled from the store (e.g, NetShare) specifically reported that the app continued to work on their phone. If Apple does have the ability to remotely disable applications and/or media, they have made a point (so far) of not exercising it.
