Who wants ads on their cell phone?

How much of a sap does one have to be to allow advertising into a device we hold in our hand? Don't get me wrong, I am an advertising evangelist, but this makes me a little nervous:

U.S. mobile advertising is expected to grow from $421 million in 2006 to $4.7 billion by 2011. Worldwide, the market is expected to expand to $11.3 billion by the same year, and it is a market ripe for business information companies.

A recent Mobile Marketing Association (MMA) survey calculated that in five years, 52% of the brands surveyed expect to spend between 5% and 25% of total marketing budget on mobile marketing. Worldwide mobile media ad spending will reach $14.4 billion by 2011, up from $1.4 billion in 2007, according to Strategy Analytics.

I smell a backlash coming.