• by Mark Walsh  @markfwal, August 4, 2011

Following its red-hot stock market debut in May, LinkedIn Thursday reported quarterly earnings as a publicly traded company for the first time. Its results did not disappoint Wall Street. The professional networking site beat analyst expectations for the second quarter, with revenue growing 120% to $121 million from $54.9 million a year ago. It posted a profit of $4.5 million, or 4 cents a share, compared to $4.3 million in the year-earlier period.

Analysts had forecast a loss of 3 cents a share on revenue of $104.7 million.

Helping to fuel LinkedIn's growth during the quarter was a 61% increase in registered users from a year ago to 115.8 million. Traffic grew 83% to 81.8 million monthly visitors and page views were up 80% to 7.1 billion.

"In the second quarter, we saw record levels of members, unique visitors, and page views, while revenue growth further accelerated," stated LinkedIn CEO Jeff Weiner. "Going forward, we plan to continue to invest in our team, technology and products in order to increase the value we deliver to members and realize the full potential of the LinkedIn platform."

The company's second-quarter performance marked a strong follow-up to its splashy IPO. LinkedIn's opening stock price of $45 more than doubled on its first day of trading in a market launch that recalled the frothiness surrounding Internet start-ups during the dot-com era. Since then, investors have remained bullish on LinkedIn's growth potential, with the stock continuing to trade more than twice its offering price.

LinkedIn makes most of its money from subscriptions and fees generated by hiring services that allow companies to recruit job candidates through the site. Almost one-third comes from advertising. The company said Thursday revenue from its hiring solutions business jumped 170% to $58.6 million from a year ago and accounted for 48% of overall sales.

Subscriptions revenue increased 60% to $23.9 million in the second quarter, making up 20% of its sales. And advertising sales more than doubled (up 111%) and represented 32% of total revenue.

In a research note previewing LinkedIn's second-quarter earnings, J.P. Morgan analyst Doug Anmuth projected the company's hiring solutions business to grow 161%, advertising, 58%, and subscriptions revenue, 37%. Based on that outlook, the level of advertising growth was clearly the biggest surprise.

LinkedIn has recently unveiled new initiatives that include a plug-in allowing users to apply for jobs on third-party sites with information directly from their LinkedIn profiles. In addition to introducing the "Apply with LinkedIn" button in June, the company earlier this year rolled out LinkedIn Today, a Twitter-like offering that allows users to stay on top of trending news tied to a particular industry or their LinkedIn connections.

Looking ahead, LinkedIn said revenue for the third quarter is projected to be in the range of $121 million to $125 million. Full-year revenue is expected to reach $475 million to $485 million. LinkedIn's shares Thursday closed down about 10%, at $95.52, before its earnings announcement. In after-hours trading, the stock was up more than 3% to $99 a share.