Earlier this week Sponsored Stories began appearing in users’ News Feeds, which demonstrates that Facebook is getting more serious about advertising. A report predicts that the social network will account for five percent of online ad spending by the end of this year.

The ad-buying and optimization firm Efficient Frontier examined data from over 15 advertisers and 20 million fans from a variety of verticals, including retail, entertainment, and consumer packaged goods.

The company found that Facebook has accounted for 2.7 percent of total online advertising spending during the fourth quarter of 2011 and believes that number will reach five percent by the end of 2012. Currently brands, on average, are gaining fans at a nine percent rate per month and this number is expected to double by December 2012.

A strong social presence can help to improve brand awareness and create a successful and sustainable life cycle for your community. Although social outreach and content creation are effective, the quality of Facebook ads is improving.

Marketers are constantly improving engagement strategies across social media platforms. As your brand continues to acquire Facebook fans, it’s worth examining your advertising budget to determine how much of it can go toward Facebook ads. You can see more data about search, mobile, and social in Efficient Frontier’s report.

[Image credit: Elyce Feliz]