For the past couple days, I was at the Card Forum & Expo in Miami. There was a lot of buzz about debit cards, alternative payments – such as BillMeLater.com and Revolution Money – as well as mobile applications.

But there was also lots of talk about the recent buyout deal -- Discover Financial Services (NYSE: DFS) agreed to purchase the Diners Club International network from Citigroup (NYSE: C). The price tag came to $165 million.

Actually, Diners Club is a pioneer, having created the first major platform for charge cards (back in 1950).

No doubt, it was mainly for the affluent, and in the world of credit cards, Diners looks more like a niche player. So why the interest from Discover?

Basically, it's a way to move more aggressively into global markets as cards from Diners are accepted in more than 185 countries.

According to Discover, the deal is expected to add $10 million to $15 million in annual pre-tax profits – which is certainly good news. So, in yesterday's trading, Discover's stock price was up 5.5% to $18.09.

Tom Taulli is the author of various books, including The Complete M&A Handbook and The Edgar Online Guide to Decoding Financial Statements. He also operates DealProfiles.com.

MOST NOTEWORTHY: Certain banks, VASCO Data Security and Bankrate were today's noteworthy downgrades:

• UBS downgraded shares of Discover (NYSE: DFS) and Capital One (NYSE: COF) to Sell from Neutral and American Express (NYSE: AXP) to Sell from Buy, as they believe a U.S.-led recession will lead to increased credit losses.
• Jefferies downgraded shares of VASCO Data Security (NASDAQ: VDSI) to Hold from Buy to reflect the company's exposure to the financial services market, as they believe 2008 will be a tough year for small companies selling into tightening IT budgets.
• Merriman lowered its rating on Bankrate (NASDAQ: RATE) to Neutral from Buy on valuation, as they believe the stock is pricing in upside from strong website traffic seen in January driven by refinance activity and Fed rate cuts. Citigroup downgraded shares to Hold from Buy on valuation, as they find the risk/reward less compelling at current levels.

OTHER DOWNGRADES:

• JP Morgan removed SanDisk (NASDAQ: SNDK) from its Top 3 Picks List.
• Goldman downgraded CSK Auto (NYSE: CAO) to Neutral from Buy and removed Google (GOOG) from its Conviction Buy List.
• Baird lowered Comerica (NYSE: CMA) to Neutral from Outperform.

MOST NOTEWORTHY: Genitope Corp, Discover Financial and Mine Safety Appliances were today's noteworthy downgrades:

• Genitope Corp (NASDAQ: GTOP) was downgraded to Underperform from Sector Perform at RBC Capital following MyVax's failure to meet its Phase III trial endpoint.
  
• Calyon downgraded shares of Discover Financial (NYSE: DFS) to Neutral from Buy citing the weak macro environment.
  
• Soleil downgraded Mine Safety Appliances (NYSE: MSA) to Hold from Buy at Soleil on valuation..

OTHER DOWNGRADES:

• Morgan Stanley downgraded Vale do Rio Doce (NYSE: RIO) to Equal Weight from Overweight.
  
• Keefe Bruyette downgraded Popular (NASDAQ: BPOP) to Underperform from Market Perform.
  
• Calyon downgraded Pride International (NYSE: PDE) to Neutral from Add.