SAN FRANCISCO (AP) — LinkedIn reported a strong fourth quarter as the online professional-networking service added 14 million members. Its net income and revenue beat Wall Street's expectations.

The results announced Thursday provided further evidence of online networking's popularity and moneymaking potential.

LinkedIn Corp.'s performance could help create even more excitement for an upcoming initial public offering of stock from Facebook Inc., which runs the Internet's largest social network. Facebook, which connects far more people than LinkedIn, filed its IPO papers last week, setting the stage for its stock market debut in May or June.

LinkedIn earned $6.9 million, or 6 cents per share, during the final three months of last year. In 2010, the company had income of $1.6 million, or 3 cents per share. It's not directly comparable because LinkedIn's outstanding shares have ballooned since its own IPO in May. Excluding the difference in outstanding shares between the two periods, LinkedIn's net income for the latest quarter increased 30 percent.

If not for certain accounting items unrelated to its ongoing business, LinkedIn said it would have earned 12 cents in the fourth quarter. That figure topped the average estimate of 7 cents per share among analysts polled by FactSet.

Revenue more than doubled from the previous year to nearly $168 million — about $8 million above analyst estimates.

Management's projections for the first quarter and full year also called for revenue above analyst forecasts.

LinkedIn, which is based in Mountain View, California, ended December with 145 members, up from 131 million in September. Since the end of the year, Linkedin said its membership has surpassed 150 million.

Investors cheered the numbers. LinkedIn's stock surged $5.31, or nearly 7 percent, to $81.70 in extended trading Thursday.