Open and closed cell aluminum foams are already used in many special applications. I've always thought a baffle tube made from open-celled aluminum foam would be a good way to suppress tube currents in CATs.
I dunno - light weight is good, but elasticity is bad. For telescope parts, you generally want as much stiffness as possible. I think you'd be better off with the carbon-fiber honeycomb sandwich laminates or other similar things with high stiffness/weight ratios rather than this. And since they are intending it for medical use, I suspect the metallic foam will be very expensive - they are going to be trying to get back the millions they are going to spend getting FDA approval...