Google's entire business depends on being squeaky clean. If they ever got caught doing "sophisticated" opinion influencing, they'd lose half their value overnight as customers switched to alternatives. And then every democratic government would join in with a serious kicking, given their elections are so vulnerable to said influencing.

I think Facebook sails very close to the wind here, but my impression is that Google's management is a lot more professional about protecting their business long term. So I'd be suprised if they tried any dirty tricks.

However, their efforts won't be limited to open letters. There will be some very high-powered lobbying going on, and I bet this letter is mostly to frame that debate to counter the lobbying from Murdoch's empire. All in all, a great time to be an Aussie politician - a lot of very expensive trips, lunches and other inducements coming there way.