Facebook (FB), once the dog of all dog stocks, is no longer a Wall Street pariah.

In fact, it's been one of the best stocks since bottoming in early September. With Thursday's close of $31.30, the shares were up 78.4% from their intraday low of $17.55 on Sept. 4. The Nasdaq-100 Index ($NDX) is flat over the same period.

On Wednesday, the shares closed at $30.59, the first close above $30 since July 13. The shares are within $7 of the  $38 offering price in its initial public offering.

The reason the stock has been rising has been expectations of decent fourth-quarter results with revenue at around $1.5 billion. That implies growth of $258 million from the third quarter, according to Jim Edwards on Business Insider. Forbes' Robert Hof sees better results as well, although there's still skepticism about the effectiveness of Facebook ads.

And there's excitement building over an event Facebook will hold Tuesday morning at its Menlo Park, Calif., headquarters. The news is a bit of a mystery. All the company would say is "Come and see what we're building." There's talk it could be a Facebook-branded phone, although CEO Mark Zuckerberg said in September a phone didn't make a lot of sense. A phone might sell several million units, but Facebook already has 1 billion users.

There is also talk about a music service, new search functionality, more features and ads for its mobile offerings, new device integration and maybe a bigger push toward gaming.

• Face time with Mark Zuckerberg?

Timothy Phillips, a technology consultant, thinks it could be Facebook getting into e-commerce via its acquisition of Karma. And he doesn't rule out that Facebook could be getting into cloud computing.

"Facebook already has one of the largest and most sophisticated data center footprints in the world," he wrote on Seeking Alpha on Thursday. The company "is keenly focused on driving the lowest cost performance per watt in the industry."

Facebook is the poster child for not buying an initial public offering on the first day of trading. The odds are you'll get a better price later.

Facebook went public on May 19 in an initial public offering fraught with problems. The Nasdaq system couldn't get the stock opened on time. There were unfilled orders and other issues. The shares hit $45 that day. When the shares bottomed in September, they were down 53% from the IPO price.

All that said, the stock has some vulnerabilities today. It is selling at significant premiums to its 150-day, 90-day and 50-day moving averages. Its relative strength index is above 70. All suggest the potential of a near-term drop.

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