A new AOL Inc. 10-K filing with the SEC today revealed the company is warning shareholders it expects lower than expected advertising revenue in 2010 from its online web properties.

AOL confirmed via the filing that total advertising revenue in Q1 2010 will be lower than Q1 2009.

The company attributed the decline in advertising revenue in both 2008 and 2009 as a direct casualty of the global financial crisis.

Total advertising revenues in 2009 were $1,748.3-million, compared to $2,096.4-million in 2008, and $2,230.6-million in 2007. 2009 advertising revenue was down materially by 17-percent compared to 2008.

In 2008, AOL reported a $1,526.6-million net loss, compared to a $248.5-million profit in fiscal 2009. Cash provided by operations in 2009 dipped to $908.2-million, from $933.6-million the year before.

AOL says it expects that the current economic conditions would continue to adversely affect advertising in 2010 as companies spend less. Annual AOL subscriber churn rates in 2007 were 4.6-percent, compared to 3.4-percent in 2009.

With just over 30-minutes until the market closes, the AOL stock (NYSE:AOL) is down more than 3.3-percent to $24.48 per share.

A recent Barclays report said U.S. advertising revenue was estimated to grow by 2.7-percent in 2010, with search advertising estimated to grow the most by up to 10-percent in 2010.

The dramatic drop in advertising revenue has prompted some publications such as the WSJ to consider restructuring their business model to subscription-based only. Rupert Murdoch, chairman and CEO of News Corporation, the parent company of the Wall Street Journal, says he would prefer loyal paying subscribers rather than marginal advertising revenue.

In mid-January 2010, The Associated Press confirmed its content would no longer be syndicated on Google News.

Essentially, publications argue content is too expensive to create, and advertising revenue is simply not sufficient right now.