Nasdaq's merger with Instinet is its first serious challenge to the New York Stock Exchange after the false start of the "stupid" takeover of Brut last year, according to one exchanges expert.

Benn Steil, director of international economics at the US Council on Foreign Relations, said linking with Instinet was a sensible move for Nasdaq. He contrasted it with the purchase of Brut, another electronic communications network, from global technology giant SunGard.