Apple has a phone and attempted a music SN.
FB has only a social network.
It seems like it could be a step in the right direction for FB, even if just to be able to compete with Google Me + Android integration
I can understand this from Google as it fits into their internet commoditization goal.
Apple's SN is all about selling more music, which is a core business for them. But to compare Apple and Google, Apple doesn't have a search engine.
WRT Ping, it's two biggest problems are:
1. Lack of FB integration; and
2. It's tied to an app (iTunes).
Apple wants (1). Betas had Facebook Connect. Rumour has it Facebook had "onerous" terms for the integration so it got killed. Lack of it is a huge problem. But that should tell you something: Apple needs FB because FB owns the much-vaunted social graph.