• by Gavin O'Malley  @mp_gavin, March 8, 2011

With its first foray into movie rentals, it's easy to assume that Facebook wants to take over the business. But while the social network is clearly exploring new revenue streams, analysts insist that Netflix and Amazon have little reason to be concerned.  

"This is clearly an experiment," said eMarketer principal analyst Debra Aho Williamson. "Facebook is exploring many different markets right now, and it's not necessarily going to be successful in all of them."

Making the experiment possible, Warner Bros. Digital Distribution began offering selected movies for purchase or rental -- using Facebook Credits -- through Warner Bros. Entertainment's Facebook movie pages.

To kick off the partnership, Facebook users can rent "The Dark Knight" through its official Facebook Page, provided they have "Liked" the blockbuster. To date, nearly 4 million users already have. For 30 Facebook Credits -- equal to $3 -- they are free to stream to movie for up to 48 hours.

Having recently created iPad, iPhone and iPod apps specifically for "The Dark Knight" and "Inception," Warner Bros. is getting creative in its efforts to reach audiences.

"Facebook has become a daily destination for hundreds of millions of people," Thomas Gewecke, president of Warner Bros. Digital Distribution, said on Tuesday. "Making our films available through Facebook is a natural extension of our digital distribution efforts. It gives consumers a simple, convenient way to access and enjoy our films through the world's largest social network."

Yet in a research note, Goldman, Sachs analyst James Mitchell said the partnership does not represent an immediate threat to Netflix or other online movie renters, since it only offers pay-per-view. It isn't available via a centralized storefront, and it can't be easily viewed on larger TV screens.

While Facebook's core business is clearly advertising, other revenue sources -- including Credits -- still make up a tiny percentage of its overall revenues. In 2010, according to eMarketer, advertising accounted for 93% of Facebook's total revenue -- a figure it expects to fall to 90% by the end of this year.

"Facebook is still looking for other revenue streams to back its core advertising business," said Williamson. "Facebook Credits will slowly increase its proportion of total revenue in the coming years. This deal shows Facebook isn't content to hinge the success of Credits solely on virtual sales in social games."

According to eMarketer estimates, Facebook's ad revenues reached $1.86 billion in 2010 -- up from $740 million in 2009. This year, eMarketer estimates the company will bring in $4.05 billion in worldwide ad revenue.

In the U.S., Facebook will account for an estimated 7.7% of overall online ad revenues in the U.S. -- up from 4.7% in 2010, eMarketer estimates.