Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Groupon (GRPN -5.41%) were soaring once again today, jumping as much as 10% after getting an upgrade from Stifel Nicolaus.

So what:  The daily deals merchant got a bump from hold, to buy, from the research firm, as analyst Jordan E. Rohan saluted the company's move away from email marketing and toward app and mobile-based business. Rohan also noted that growth is improving in Groupon's local North American business, and stabilizing in Europe, as the company builds out newer segments such as Groupon Goods, direct-selling products, and Groupon Reserve, which handles restaurant reservations.

Now what: Groupon shares are now up nearly 400% since Founder and former CEO Andrew Mason was ousted from the company earlier this year, but the online dealer has delivered little in the way of profits, or measurable improvements, since then. Rohan argues that Groupon is the leader in mobile commerce, but Groupon has been in that position basically since its inception, and that hasn't been enough to create profits. Market share is not a guarantee of a successful business, and revenue growth has slowed dramatically. Despite the company's improvements under new CEO Eric Lefkofsky, it still seems to be searching for a profitable business model. I'd stay away until it gets that figured out.