As a new member of the Nasdaq 100 index, Facebook's comeback may get a boost on Wall Street.

The closely watched index represents the 100 most valuable, non-financial stocks trading on Nasdaq. Facebook shares will be added Dec. 12.

Analysts say being in the Nasdaq 100 is a potential boon for shares of the No. 1 social-networking giant.

The Nasdaq 100 is a Who's Who of big technology companies, such as Apple, Google and Microsoft.

Bigchunks of Nasdaq 100 company shares are often bought and held long termby exchange traded funds and major mutual funds that invest mostly oronly in key stock indexes.

Inclusion in the index could even beconsidered a victory for Facebook, which has struggled mightily toappeal to investors since its May 18 initial public offering that was mired in technical problems.

"Thecompany is a lot more seasoned now," says Francis Gaskins of IPODesktop Premium, a website devoted to IPOs. Being in the Nasdaq 100"takes away some of the stain of the botched IPO."

Facebook'saddition to the the Nasdaq 100 underscores the company's stock pricerebound. Shares made their debut at $38 apiece, but quickly fell apartas investors discovered more about the IPO's problems and began to worryabout the company's strategy to make money off its massive base ofusers.

The shares peaked at $43 but then plummeted to just under $17.75 a share in September.

Facebook stock finished up 25 cents, 0.9%, to $27.71 Wednesday, 44% higher than the stock's recent Nov. 9 low of $19.21 apiece.

The stock has rallied in recent weeks, despite concerns about a series of post-IPO lockup expirationsthat released hundreds of millions of shares for sale on the openmarket. Many feared the huge supply rush would push Facebook's shareseven lower.

Now, investors who build portfolios based on theNasdaq 100 are likely to take a closer look at the stock, says JosephBonner of Argus Research in an e-mail to USA TODAY.

"Inclusionin the Nasdaq 100 should be a positive for (Facebook), since a bunch ofindex funds and ETFs now have to buy to maintain a match with thebenchmark," Bonner says.

The exchange rebalances the Nasdaq 100index each year as the values of companies in it change. Facebook isjoining the Nasdaq 100 early due to the departure of outsourcing firmInfosys, which is moving to the larger New York Stock Exchange.

Includingall classes of its stock, Facebook would rank 13th in the index, with amarket value of nearly $60 billion, behind eBay but ahead of News Corp.

Including only Facebook's A shares, valued at $30 billion, the company would be the 24th most valuable company in the index.

Apple, even after its $37.05 fall, 6.4%, to $538.79 Wednesday, remains the most valuable stock in the index, with a $516 billion market value.

Investors had largely anticipated Facebook's additionto the index this year, explaining why there wasn't more reaction tothe announcement, says Josef Schuster of IPO tracker IPOX Schuster.

Investorsare likely far more interested in when Facebook might be added to thebroader Standard and Poor's 500 index, which isn't likely anytime soon,Schuster says. "The S&P is much more important."