They mentioned a lot of colos, but you can actually lease space in the NYSE building itself. You don't get much faster than parking your server next to the one logging the transactions!
One reason the high-frequency traders can beat others to the punch is that they often locate their computers in data centers run by the exchanges. The New York Stock Exchange, for example, moved its computer infrastructure last year to a facility it built in Mahwah, N.J., where it also leases space to trading firms. It can command premium prices for that space because close physical proximity means fast access to the exchange's raw trading data. Most other market participants don't see that data until milliseconds later, after it's been consolidated and combined with information from other exchanges.
...this aint no FB/Google/blah.1M.requests.a.minute datacenter - its the latency not the thoughput that matters.