"What makes the terminals so popular on Wall Street is not just their comprehensive data, but their social value. The Bloomberg terminal is like the Facebook of Wall Street; a social tool that connects the financial world. The trading terminal has one major advantage: Bloomberg Instant, a widely popular chat/messaging system that Bloomberg sells as instant access to important people, and logs 200m messages - or 15m to 20m chats a day among 310,000 subscribers. Here's the ad copy on it, which gives you a sense of what Bloomberg is really selling through its terminals: influence."

This is one reason the market moves so fast; there are 310,000 big money smart money people efficiently connected and getting information faster than those not plugged into this expensive network.