Facebook Hums Along, Eyes Phase Two - Businessweek

From a related summary in the WSJ, "Facebook shares, which initially rose as much as 15% in after-hours trading, later lost those gains as Facebook executives discussed the results with analysts and investors. The shares fell about 1.6% from a 4 p.m. closing price of $49.01."

"On Wednesday Facebook far exceeded expectations when it reported its quarterly earnings. The company made $2.02 billion in revenue (investors expected $1.91 billion), 49 percent of which came from mobile. Its monthly active users grew 18 percent over the last year to 1.19 billion. Every day 728 million people use Facebook, with 507 million people logging onto mobile.
The company did sneak in one ominous tidbit: its growth among American teenagers has flattened, and the company is actually losing users among younger teens. The company said it wouldn’t be regularly updating investors on what was going on with young users, because the numbers may not be reliable."

Facebook Hums Along, Eyes Phase Two - Businessweek