According to research firm eMarketer, more than half of adult internet users in the US logged into Facebook at least once per month last year. They project an increase of 13.4% this year, meaning Facebook will reach 9 in 10 social network users.

Just as impressive, ad spending on Facebook will rise to $2.19 billion in the United States this year, and around $4 billion worldwide, doubling numbers from last year.

These stats confirm that Facebook is the place to be when it comes to building your online marketing presence.  Will these trends continue or will Facebook be overtaken by another platform like Myspace before it?