The New York Stock Exchange and its German counterpart Deutsche Borse have agreed on a $10 billion merger that will effectively combine two the world's most important stock exchanges. The news comes a week after London and Toronto's exchanges announced a similar deal. So why are these major financial institutions joining forces and what will the global stock market look life after the deals go through?

Louise Story, Wall Street and Finance Reporter for our partner The New York Times, says these mergers are a sign of things to come and that eventually she wouldn't be surprised to see yet another merger between the trans-Atlantic exchanges and exchanges in the Asian stock markets. It's a system that's catching up with the way global commerce works.