Expectations were astronomically high for LinkedIn’s first quarter 2012 earnings, and the professional social network more than delivered with $188.5 million in revenue and net income of $5 million.

The revenue figure is up 101 percent from the same quarter last year and represents the seventh straight quarter of greater than 100 percent year-over-year growth for the company. Net income more than doubled, growing from $2.1 million in the first quarter of 2011.

“We saw strength across all key metrics from member signups and engagement to significant revenue growth across our three product lines,” LinkedIn CEO Jeff Weiner said in statement.

Analysts projected that LinkedIn would report earnings of $0.09 a share on revenue of $178.8 million for the quarter. LinkedIn, however, posted Q1 earnings of $0.15 a share on revenue of $188.5 million.

LinkedIn is making a majority of its revenue (54 percent in Q1) from its hiring solutions. The products’ combined revenue for the quarter totalled $102.6 million. The company made $48 million from marketing services and $37.9 million from premium subscriptions in Q1.

In an earnings conference call Thursday afternoon, Weiner said that LinkedIn, which has 161 million members, saw 58 percent year-over-year growth in member sign-ups, and is adding new members at a rate of two per second. More than 60,000 developers are using the company’s APIs, Weiner added.

The professional network said that revenue for the second quarter of 2012 is projected to range between $210 million to $215 million, and also upped its full-year 2012 revenue guidance range to $880 million to $900 million.

Today’s earnings report came on the heels of news that the company would be acquiring presentation-sharing startup SlideShare for $119 million in cash and stock.

LinkedIn’s stock is up nearly 3 percent in after-hours trading. LinkedIn earned $167.7 million in revenue during the fourth quarter of 2011.

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