However faint? Believe me, if there is a weakness it will be found. Things are always in the last place you think to look because you stop looking afterwards. Hackers are no different and won't stop either so this plug merely makes them move along until they find the next flaw.
The real weakness, or maybe the biggest bullseye, is connecting ALL things G together with one password to begin with. It makes you want to limit how many Google services you use, email and adsense account for example... do they really need the same password ?