Google's Android OS is the hottest new mobile platform on the market, at least as far as publishers and marketers are concerned.

Microsoft's Windows 7 Phone Revealed

More content producers plan to add Android to their list of supported platforms than any other OS next year, according to a survey released this week by Digiday, Stifel Nicolaus, and Millennial Media.

55% of advertisers surveyed and 14% of publishers plan to add Android support, 45% of advertisers and 10% of publishers plan to add Windows Phone 7 support, while 45% of advertisers and 10% of publishers intend to add iPad support.

The survey, which polled 600 media and advertising professionals, also found that 21% of advertisers and 4% of publishers will add iPhone support, and 17% of advertisers and 6% of publishers will add support for RIM's BlackBerry OS. Many publishers and advertisers already support the iPhone and BlackBerry, so those numbers were not included in the survey results.

The survey's findings could be seen as a blow to Microsoft, which needs to build momentum behind Windows Phone 7 in a hurry. If it fails to do so, Redmond's new mobile platform could quickly go the way of its KIN line of phones, which was pulled from the market earlier this year amid dismal sales.

Windows Phone 7 devices from Samsung, LG, and HTC went on sale in the U.S. on Monday on the AT&T and T-Mobile networks. One unconfirmed report that's been widely cited by bloggers pegged first-day sales at 40,000 units. If accurate, the total would represent a decent debut for Windows Phone 7, but hardly one that could be considered a blockbuster.

Apple, after all, has said it sold roughly 143,000 iPhone 4s per day during that device's first three weeks on the market earlier this year.

Gartner predicts the release of Windows Phone 7 will help bump Microsoft's share of the worldwide mobile OS market from 4.7% in 2010 to 5.2% in 2011, but says the company's share will ultimately decline to just 3.9% by 2014.