NYSE Euronext (NYX), which competes with Nasdaq OMX (NDAQ) and CME Group (CME), is the world's leading stock exchange in cash trading, both in terms of volume and value. NYSE provides the trading platform and services for trade execution of stocks listed on its exchanges -- NYSE, NYSE Arca, NYSE Amex -- as well as for orders that are routed to other market centers for execution. It charges transaction fees for executing these trades.

Due to the global economic downturn, NYSE Euronext's EBITDA margin from its cash equity trades in its U.S. exchanges tumbled from around 38% in 2006 to -4.2% in 2009. The margin recovered a bit in 2010, and we expect it to increase slightly in the short term and stabilize thereafter, owing to fierce pricing competition among stock exchanges to gain more volumes. NYSE Euronext could however benefit from economies of scale from its merger with Deutsche Boerse (DBOEY), which can push its margin higher.

NYSE Euronext (NYX) and Deutsche Boerse AG of Germany recently announced a merger that will create the world's largest financial exchange. NYSE is the world's largest stock exchange in the world by market capitalization of its listed companies and Deutsche Boerse AG is the largest stock exchange operator in Germany. NYSE Euronext's main competitors are Nasdaq OMX (NDAQ) and CME Group (CME).

We have a price estimate of $34.77 for NYSE Euronext's stock, which stands below market price.

Last December, over 100 stocks were featured in our Top Picks for 2007 report. Now, at mid-year, we turn to the 20 advisors whose picks showed the strongest gains to get an update on their previous picks, as well as a new favorite stock for the second half of the year.

Bernie Schaeffer, editor of Schaeffers Investment Research, chose International Securities Exchange (NYSE: ISE) as his top pick for 2007. The stock has risen 40% on news that Deutsche Boerse AG plans to acquire the firm. For those who own the stock, Schaeffer recommends selling.

For his new favorite idea, the advisor turns to electronics retailer RadioShack Corp. (NYSE: RSH). He explains, "The stock has been flying high in 2007, doubling in value in less than six months and moving to a two-year high. Throughout this impressive rally, the stock has enjoyed the reliable support of its 10-day and 20-day moving averages.

"RSH shares have also benefited from their 10-week moving average, which neatly guided the equity higher following a late-April pullback in the shares.

"This performance has clearly dwarfed the accomplishments of the broader retail sector. RadioShack's weekly relative-strength measure, as compared to the AMEX Retail HOLDRs Trust, has been on the rise since January and is now at a 26-month high.

"The company has been impressive in the earnings confessional as well. RadioShack's first-quarter earnings, reported in late April, hit 31 cents per share, well above year-ago results of 6 cents per share and easily better than analysts' consensus view of 14 cents per share.