Ad sales have always gone up and down with the economy.

VOA: special.2009.03.21

But smaller screen sizes than PCs, less sophisticated ad targeting and wariness by advertisers is holding down ad rates or spending on mobile devices.

WSJ: Twitter's Mobile Ads Begin to Click

Typically accountability for effectiveness has pushed down ad prices.

FORBES: Winners & Losers In Google TV

In the end, the winners may prove to be online advertisers, who will see the potential for resulting stronger competition for Google to drive down ad rates and provide new advertising services.

FORBES: A Messy Marriage