Twitter's Growth Pales in Comparison to Facebook's
The good news for Twitter is that its revenue is growing much quicker than its active user base. Q4 revenue almost doubled to $479 million, beating analyst expectations by a healthy margin. So while Twitter will probably never match Facebook’s near universal reach, the company has proven once again that its business model is working, albeit at a smaller scale.
This chart compares Twitter's recent user growth to Facebook's user growth between 2009 and 2010.