According to a widely cited analyst report at mobileSQUARED, Facebook’s mobile business will be mammoth this year. Globally, there’s the $1.2 billion figure. In the US alone, the company is predicted to do $653.7 million worth of ad sales on mobile. That figure is shocking because all of mobile ad sales last year in the US just barely topped $1 billion. Equally as impressive, though is the reach–100 million of Facebook’s users access the site via mobile devices. [Source: mobileSQUARED]