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Just because USB 3.0 is available now doesn't mean that old E-SATA devices won't work, and the full speed benefits of USB 3 will not be available to anyone using SATA3 devices instead of devices with a SATA6 interface, which are also newer and not yet available everywhere. The reason you don't see more E-SATA is that most people are happy with the USB 2.0 devices and ports they already have. I wouldn't hold my breath on E-SATA's long-term future, since USB 3.0 ports are backawards-compatible.