American Express (AXP) followed in Visa's (V) steps and announced a digital payment and commerce platform dubbed Serve, which enables the consumers to make purchases and person-to-person payments online via mobile phones and at merchants that accept American Express cards. MasterCard (MA) is also planning to launch its own offering for personal payments.

We estimate that American Express derives 73% of our $49.61 price estimate from card transaction and execution fees while Visa derives almost 29% of its $85.03 Trefis price estimate from transaction fees.

When it comes to credit-card businesses, I'm partial to Visa, Inc. (V). Even so, I have to give my respect today to Discover Financial Services (DFS). At the time of this writing, the stock was up 4.5% to $23.26. Volume was strong. Furthermore, a new 52-week high of $23.46 was recorded earlier in the day (by the time this is published, it's possible the high quote will be different).

The stock has been a good holding over the last twelve months. The 52-week low is $12.11, and the one-year chart shows strength. This name is heading for a double. Is it too late to buy?

Let's take a quick look at two companies that posted quarterly reports. One makes its money from plastic (the kind you use to buy things), the other serves pizza, poultry, and tacos to the masses.

Visa, Inc. (V) has not been a great stock this year. Its 52-week low is $64.90 and its 52-week high is $97.19. The stock closed today's regular session at $72.09, backed by unremarkable volume. I don't know, maybe I'm way off, but I think this name should be at least a little closer to the 52-week high. On a related note, the one-year chart is not what shareholders want to see.

Analyst Upgrades

• Oracle (ORCL) to outperform from perform at Oppenheimer.
• Accenture (ACN) to buy from hold at Jefferies.
• Advanced Energy (AEIS) and Applied Materials (AMAT) to overweight from equal weight at Barclays.
• Spreadtrum (SPRD) to buy from hold at Auriga.
• Healthcare Realty Trust (HR) and Tortoise Energy Capital (TYY) to outperform from neutral at RW Baird.
• Global Payments (GPN) to equal weight from underweight at Morgan Stanley.
• CBS (CBS) to buy from neutral at BofA/Merrill.
• Sonic (SONC) to outperform from neutral at Cowen.

The earnings crunch continues this week, and analysts surveyed by Thomson Reuters are anticipating lots of strong quarterly reports.

For example, year-over-year earnings growth from big oil Chevron (CVX), ConocoPhillips (COP), ExxonMobil (XOM) and Royal Dutch Shell (RDS.A) are expected to be in double digits. The same is true of many other energy and mining concerns reporting this week: Allegheny Technologies (ATI), Alliant Energy (LNT), Arch Coal (ACI), Cliffs Natural Resources (CLF), CMS Energy (CMS), CONSOL Energy (CNX), DPL (DPL), Hess Corp. (HES), Minerals Technologies (MTX), Pioneer Natural Resources (PXD), PPL Corp. (PPL), Southwestern Energy (SWN), Total (TOT), Whiting Petroleum (WLL), Williams Companies (WMB) and Wisconsin Energy (WEC).

"Credit card demand has exploded in recent years. Today, credit cards are responsible for over $2.5 trillion in transactions each year," notes Ian Wyatt.

The editor of Top Stock Insights explains, "And no company is better positioned to capture the digital transaction market than Visa (V); further, investors have a window of opportunity right now to pick up shares at a great price.

"Different from credit card-issuers, Visa is shielded from the consumer credit troubles (such as delinquencies and defaults) because they don't lend to consumers.

Discover Financial Services (DFS) is trading higher this afternoon after the credit-card entity reported numbers for the fiscal third quarter. At the time of this writing, the stock was up 2.4% to $15.95. Volume was very strong.

The shares have traded in a narrow range over the last twelve months. The 52-week low is $12.11 while the 52-week high is $17.36. The chart shows a nice trading vehicle for those who like to buy and sell on a short-term basis.

Analyst Upgrades

• Goldman upgraded Costco (COST) to buy from neutral based on valuation, improving fundamentals and potential catalysts. The firm raised its price target to $68 from $62.
• Soleil upgraded MGM Resorts (MGM) to buy from hold, citing valuation, easing balance sheet concerns and a multiyear convention recovery. The firm upped its target for shares to $14 from $13. Note, Soleil also downgraded Las Vegas Sands (LVS) to hold from buy.
• Piper Jaffray upgraded Phillips-Van Heusen (PVH) to overweight from neutral with a $59 price target following the company's better-than-expected Q2 results.
• Dell (DELL) was upgraded to buy from outperform at CLSA.
• CommScope (CTV) was upgraded to buy from neutral at UBS.
• EnCana (ECA) was upgraded to sector outperformer from sector performer at CIBC.

I found a rather interesting article on Bloomberg, one discussing the potential of smartphones to replace credit cards. Supposedly, both AT&T (T), Verizon (VZ), and perhaps T-Mobile, may work with Discover Financial Services (DFS) and Barclays (BCS) in Atlanta and three other cities to test a system allowing consumers to pay with the "wave of a smartphone." This move would be the largest effort to attempt mobile payments in America and could serve to cut into credit card use.

Crone Consulting, a credit card consultant, noted that such a move could be a "game-changer" as far as credit cards are concerned. Think of how much such a move could cut into the market share for credit cards. According to the article, Visa (V) and MasterCard (MA) handled 82% of U.S. consumer spending a year ago (that is $2.45 trillion). Now imagine that smartphone users have the ability to simply pass their phone over a reader in order to pay for their purchases.