Popular social-networking site Facebook is the latest Internet company rumored to be preparing to go public, causing some investors to wonder if there’s a tech IPO revival on the way.

Facebook expects to hit the 500-shareholder threshold that would trigger regulations prompting it to publicly disclose financial statements and launch an initial public offering next year, according to a document given to potential private investors by Goldman Sachs, Reuters reports. USA Today confirmed the existence of the letter but could not obtain a copy.

Facebook and Goldman Sachs declined to comment. But market watchers say Facebook’s path is clearly leading toward an IPO. "Facebook is on the runway; they just don’t want to say, ‘Here we go. Watch us,’" says Francis Gaskins of IPOdesktop.

If Facebook did go public, it would continue a reluctant return of technology companies to the IPO market. Last year, 45 U.S. tech and communications companies went public, up from 16 in 2009 and just four in 2008, says Renaissance Capital. That’s still just two-thirds of the 68 tech and communications companies that went public in 2007, the year the broad stock market peaked.

Facebook, though, isn’t the only Internet company eyeing an IPO. Internet communications company Skype last August filed to go public. And Facebook is the second tech heavyweight this week to be linked to a possible IPO. On Wednesday, Reuters reported LinkedIn, the social-networking service for professionals, was mulling an offering. LinkedIn declined to comment on the story.

It’s far from a tech IPO bonanza. The tech IPO market is still a ghost of what it was during the dot-com boom. In 1999, 272 Internet companies went public, as did 152 more in 2000, says Jay Ritter, professor of finance at the University of Florida.

Yet, Facebook’s prospective IPO is an about-face for the company, whose CEO, Mark Zuckerberg, had repeatedly downplayed the idea. Facebook and online game maker Zynga are among a handful of mature start-ups that have eschewed public offerings despite the recent uptick in tech IPOs. They have thrived on a new breed of private-equity investments for funding.

Facebook’s private offering through Goldman shows the company is likely mulling an IPO but isn’t in a hurry, says Nick Einhorn at Renaissance Capital: "They might think they can get a higher valuation when they go public if they wait a little more."

The company may very well need more time to generate the level of revenue and earnings needed to justify its private valuation, estimated to be around $50 billion, Gaskins says. "Facebook’s valuation is ahead of its revenue right now," he says. "It may not be in a year."

And even if Facebook and the other Internet companies weighing IPOs are successful, market watchers don’t anticipate a replay of the dot-com IPO boom of 2000, when very small Internet companies rushed to go public. There is "no iconic IPO that will open the floodgates," says Bill Gurley, a partner at venture-capital firm Benchmark Capital.