Aside from HDV-to-HDV over firewire, Do any of the currently available HD cameras (pro, prosumer, or consumer) have facility and mode to record an incoming HD stream?

Any camera with an HD-SDI/SDI out you can capture with a capture card no problem and that is basically all of the pro cameras on the market.

Via what method are you looking to capture?

I'm talking about the other way... the camera recording an incoming video signal, functioning more or less as a deck. Most everything DV or HDV has/had this capability, but I'm not sure more modern tapeless cameras do. I know my HVX would only capture to DV tape, but not P2...

Are there any cameras that do this? None that I am aware. Capture devices are a whole different category of the market.

That used to be an option on older SD ENG camera's.. Having a CVBS (Composite) input for pool feeding...

I just searched for a bit and found out that the PDW-700 and PDW-F800 have an option for HD-SDI in:
"For pool-feed operations, the optional CBK-HD01 and CBK-SC02 boards provide HD- and SD-SDI inputs, and SD composite input respectively."

Another search showed me that atleast the following cameras can do SDI recording as well: HPX-3100, HPX-2000 (as an option board)...

I doubt lower end camera's offer this, unless it's firewire based or similar.