Are my devices really broadcasting the SSIDs they have been connecting to?
If you use WPA2 PSK and choose a long, random password (you want enough entropy that brute forcing it is impossible - for example, 20 completely random and independent characters taken from a dictionary of 62 characters gives you ~105 bits of entropy, which should be enough, while 8 characters or a few dictionary words might not cut it) impersonating your phone is not feasible if your laptop is configured to only ever connect using the saved pre-shared key.
Not only is a "hidden" AP not really hidden at all, it makes a lot of functionality much more difficult, such as channel choosing and reconnect.
At least for Android, someone else agrees: http://code.google.com/p/android/issues/detail?id=65890
Now that you have your fingerprint, you can leave a few scanners around where you're trying to track the congressmen. IE, if you want to blackmail, put it around strip clubs.
Seems like a major security hole to me.
Due to the extremely narrow circumstances [1] under which the MAC address randomization is actually used, the feature may as well not exist.
Exactly, even if it's not broadcasting network names, almost every student in the Netherlands will have the train's WiFi hotspot in their list of networks.
One thing I still want to check out is whether the laptop will connect to an open network with the same name as a known network that was password protected.
Keep in mind that your devices are also broadcasting a variety of globally unique identifiers everywhere you go.