http://online.wsj.com/article/SB116615315551251136.html?mod=hpp_us_pageone Very interesting read with regards to the speed issue in trading.... This brings up an interesting question of why would one have a bid ask spread at all.... Obviously....if a small firm such as BATS can enter the market....it would seem that the next step is to have a singular price structure....where there would be some form of a small monthly fee very much like the data fees that are paid today.... Perhaps the next model will be a combination of some small monthly fee which is accompanied by advertising... With the mergers of the worlds exchanges...the further elimination of the human hand ....maybe traders will end up paying for trading by paying a small monthly fee...or maybe nothing at all........ In 2000...one was paying $15 per trade.....In 2006 one pays $2.00.....in two years....possibly nothing....