Accodring to this article, after Apple's iPhone, google are considering what would ammount to a "gPhone", a google phone.
The article talks about hearing ads as you make a call, which I don't see as such a good idea: google has (up to this moment) made a big effort to make sure their ads don't become annoying. This is a sound business decision, as the other adds providers are now fighting an upstream battle against adds-banners filtering, Adblock-type extensions to browsers supporting them, and banner filtering though transparent proxies (there might be other solutions available).
Still, that's not the only thing google could do. If I were in charge of this initiative, I wouldn't make the users listen to voice recordings (as everybody knows how hated telemarketers can get, and google would lose business if they became associated with that annoyance). Instead, they could create phone color themes with a different logo each week (for example), put an icon with offers in a corner of the screen, dynamically upload screen-savers to the phones and a whole set of other options of that type.
Additionally, they could create a dynamic price plan (say ... you pay for 45% of your bill, and only receive commercials at night, or have to answer a survey every now and then).
Either way, it seems like a good idea for business expansion on their part (if they don't botch it up).