How to other pre/pros & receives handle the component inputs? I always assumed they were assignable, like the digital inputs, and would take the place of a composite/s-video plug pair.

Interestingly, if they were assignable... and you had one component video input assigned to "DVD" and one optical input also assigned to "DVD," you'd have both the analog audio and composite/s-video inputs for "DVD" unused. It's a shame you couldn't use that for a 10th input.