By Vince Hill

PHILADELPHIA (CBS) — Facebook, the social networking web site, may be filing its long-awaited initial public offering (“IPO”) later this week.  But it will probably be months before the company will be offering any stock.

The Facebook IPO is expected to be big — really big.  Dan Gallagher, tech editor at Marketwatch.com, says the keyword here is expected.

“We don’t really know until we actually see a filing and see how many shares they propose to sell and what they assume their valuation range to be,” he tells KYW Newsradio.  “But it’s very likely to be big financially.  But in terms of the impact on the market and its visibility, it’s probably going to be one of the biggest events this year for sure.”

Gallagher says Facebook first has to file the offering, and then there will be several weeks and months of investor meetings to decide where they want to price the stock and when they want to release it.

But Gallagher says this type of valuation is a first — there’s nothing out there now to gauge it against.

“LinkedIn went public last year, and they’re in a similar business, but they have some different revenue models.  We saw IPOs from Zinga and Groupon, which are kind of the same space but don’t do the same exact thing.  So, it’s really hard to predict who’s going to have what kind of effect.”

Want to get in on the ground floor?  Jill Schlesinger, editor-at-large at Moneywatch.com, says don’t hold your breath.

“The big underwriters, Goldman Sachs and Morgan Stanley — I believe Morgan Stanley is going to be the lead — what they’re job is, they take the stock from the company and they distribute it.  Now, they’re not going distribute it to the average Joe like you and me, what they’re going to do is they’re going to go to their very best and biggest clients and try to offer them the shares.”

Reports indicate the IPO could raise as much as $10 billion for Facebook and value the company at $75 billion to $100 billion.

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