In the video below, Motley Fool financial analysts David Hanson and Matt Koppenheffer discuss why today's market environment could make Charles Schwab (NYSE:SCHW) and TD Ameritrade (NASDAQ:AMTD) two very interesting plays.

David tells us that increasing investor optimism in the market could lead to an increased number of brokerage accounts being opened with these two discount retail brokerages, as well as an increased number of trades being made by those account holders, which generates increased revenue in fees. Also, as the Fed looks to end its quantitative easing program later this year, interest rates are expected to rise, which will mean that the large balances these companies hold as assets will suddenly be collecting far more interest. David tells investors about these two investment catalysts in detail, and gives us one important thing to look for to see if this investment thesis is playing out.