In the meantime, a ping of 50ms is an eternity for most financial applications. For normal algorithmic/quant trading you usually want to stay under 10ms roundtrip. For HFT, anything above 100µs is pretty slow. Gives you some perspective.
It was more a reference to the required latency from message received on wire, to messages processed, routed and dispatched on wire - for the scale, rather than physical location and speed of light issues.
