Any word on whether using Google-Voice would be a good safeguard against this? Presumably, because your google-voice account is so intrinsically linked to your Google account, which is much harder to hack, that should mitigate this threat tremendously. Especially if you're using google-voice to forward all calls to a number that no one else knows about.
I would not use Google voice. I'm not sure, but I doubt Google controls the major component in the international mechanism responsible for routing telephone calls. I would expect that they outsource some of the mechanisms to 3rd parties.
