Don't look now, but Groupon (NASDAQ:GRPN) may finally be a Wall Street darling.

Shares of the daily deals leader have soared 30% through the first three trading days of this holiday shortened week. The stock has risen in each of the past six trading days, surging 48% higher in that time.

What's going on? Were the bulls right all along? Are the gains sustainable?

Well, finding the catalysts for the pop is easy.

  • Hedge fund operator Tiger Global Management has accumulated a 9.9% stake in the company.
  • Groupon opened its first concept store -- a physical storefront where shoppers can redeem lifestyle products and test the products out -- in Hong Kong.
  • The stock began this six-day rally after closing nearly 87% below last year's IPO price of $20.

Now, clearly the first two points wouldn't have had a material impact on the stock if the third point wasn't in play. Many investors see the daily deals leader as a Groupon-esque markdown itself.

That's dangerous.

The Groupon model that generated the pre-IPO buzz last year is toast. Groupon's flagship vouchers for local outings -- its bread-and-butter source of non-direct revenue -- has actually posted declining revenue in back-to-back quarters. Groupon's top-line growth these days is coming entirely from Groupon Goods, where it's more like Overstock.com (NASDAQ:OSTK) in offering closeouts and overstocks than in selling discounted spa services or restaurant experiences.

This isn't necessarily a bad place to be. Overstock.com's stock has nearly tripled since bottoming out in March. It's a niche where Groupon can capitalize on its massive mailing list of bargain hunters, serving them deals on physical goods without having to worry about remorseful merchants on disappointed buyers that let expirations run out after ill-advised impulse purchases.

The margins may not be as spectacular as the original model where Groupon would take nearly half of the value of the pre-paid vouchers as a middleman marketer, but it's not as if that model ever paid off the way that investors figured it would.

LivingSocial -- the country's second-largest player in daily deals -- isn't publicly traded, but its finances are made public because Amazon.com (NASDAQ:AMZN) has a sizable stake in the company. The bad news for Amazon is that LivingSocial is also failing to live up to initial expectations.

There's a reason why many dot-com titans that originally embraced the Groupon model in pursuit of incremental business have largely abandoned the revenue stream.

This makes assessing Groupon's chances from here difficult. New initiatives -- including the concept store, Groupon Goods, and the recent push into arming merchants with a cost-effective transaction platform -- are the real drivers of Groupon now.

There are risks there, but at least Groupon isn't relying in the downward spiral that flash sales have become. Groupon has a shot, but it's a shot with high risks in the pursuit of high returns.

Longtime Fool contributor Rick Aristotle Munarriz has no positions in the stocks mentioned above. The Motley Fool owns shares of Amazon.com. Motley Fool newsletter services recommend Amazon.com and Overstock.com. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.