I've previously read suggestions for running a virtual machine from an external hard drive to increase performance. With this in mind, I'm curious what the introduction of a new technology like Thunderbolt will do to this.
I know that it can't hurt performance, but I'm curious about this -- as slow as hard disk drives are (perhaps ~100 or 200 MBps?), how noticeable of a performance difference could there be for operating a virtual machine? If USB (even 2.0) transfers faster than the disk can transfer, isn't the bottleneck already the hard drive?
Note: I know that solid-state drives introduce an entirely new situation; I'm not referring to them.