Advertising on social networks grew almost 34 percent to $1.2 billion in 2008, per eMarketer, but despite projections of continued growth, the pace is about to slow significantly.
For 2009, eMarketer projects a 10 percent rise in social-net ad spending to slightly less than $1.3 billion. Growth in the space for 2010 will be even more sluggish at approximately 3 percent to $1.33 billion, eMarketer said.
By 2013, U.S. marketers are expected to spend $1.6 billion on social network advertising.
Advertising is not the only way for marketers to participate in social networks, however. Marketers will still need to be where their customers are, and consumers remain heavily involved in online communities.