To come back to an <off-topic> remark I made in another thread; ".....like the annoying MAC address spoof of the iPhone". I was not quit explicit, the fact that they spoofed your MAC (they call it enable a Private address) can be IMHO an addition to anonymity or enhance privacy, but what I found "annoying" is the fact that it was not announced, so without any warning/information (or maybe I have missed it) they just enabled it by default. As my network works with IP reservation (MAC), this sudden change was quit "annoying".
When you distrust such large companies, you could come up with the idea that, after the introduction of a "new" MAC address, the only one that can still follow your path is the company, that from that moment on, has the exclusive of this unique address..... ...and we may never resolve this, as it is closed source.