If there ever was any question that social networking is slowing down, Facebook's chief executive officer Mark Zuckerberg dispelled the notion in an interview published Monday. Zuckerberg said Facebook plans to increase its staff by as much as 50% this year.

Even as early Facebook employees are moving to cash out of their company stock, the startup has been aggressively hiring new employees as its user base has grown to more than 250 million. In an interview on Bloomberg.com, Zuckerberg said his company is taking advantage of the large crop of engineers who have been laid off in the current economic downturn.

"No one else has been hiring," said Zuckerberg. "It's been a great environment for us because the economy has helped out The thing I want to remind people of is we're way closer to the beginning than the end."

Facebook's hiring spree runs counter to the experience of its social networking rival MySpace, which recently announced it would trim its international workforce by two-thirds and its US staff by 30%. And, a recent informal survey at an Enterprise 2.0 session found that participants were cutting back on their use of Facebook as well as MySpace.

However, Facebook's user base continues to grow and its workforce has reached the 1,000 mark to keep up. Earlier this year, company executives said Facebook expected to grow 70% this year with revenues surpassing $500 million. Facebook generates revenue from advertising and other payments.

Facebook, which is still privately-held, has approved a measure for early employees to sell some of their company shares through a program with Russian investment firm Digital Sky Technologies, which has been acquiring Facebook shares. The Digital Sky investment valued Facebook at $6.5 billion.

"We didn't take that round of financing with any particular goal in mind," said Zuckerberg. "We think of that mostly as a buffer."

Started by Zuckerberg in 2004 in a Harvard University undergraduate dormitory, the company has enjoyed explosive growth since then. The company headquarters has been moved to Palo Alto.

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