The 4th quarter is a critical, a seasonal time for Ad sales (Christmas).
One of the reasons is the growth in mobile search where users access Google by smartphone and those CPC rates are always lower. So if you like, the averages are down because of "blended product". Or in other words, an increase in its lower-cost product brings the overall price down.
It has already sold the Motorola set-top TV business for just over 2 billion usd.
It came too on the day that RIM who owns Blackberry Crackberry, say that they'll launch their new phone on January 30th. And that, in contrast to Google, is really make or break time.
But this is all good.