Today, I discovered this by accident and wonder if it is well known. On my iMac in the system settings, under Networks - advanced I saw networks listed that I have accessed with my iPhone the past months (hotels, restaurants and the like). It appears that these preferred network settings are synced via iCloud. I had no idea about this before An advantage is that I can clean up the list on my iPhone on my iMac by deleting old network settings (on the iPhone itself, you can only forget a network if you're connected as far as I know). This only works if these changes are synced back of course. This is on Mavericks 10.9.5 by the way.