I know that the Kenwood Soverign line did conversions from composite and s-video to component.
A feature like this is going to be limited in its benefits. Since the signal is already generated in a S-Video format, it is only the original S-Video signal that can be divided up. Your signal through the component cables will not be of greater quality than what you have fed it with the S-Video cable.
Unless you have a really high end video processor, I'd view format conversion as a novelty rather than as conferring any tangible benefit. My pre-amp/processor (Casablanca) switches s-video and composite, and, if I wanted, I could get a board to switch component. Frankly tho', I've got more component inputs on my TV than sources anyway so right now I just run my component sources directly into the TV. My girlfriend doesn't care that much about video quality, so I also run s-video to the pre-amp so she can switch video without bothering with selecting the input on the TV remote.
Suppose my preamp did do a format conversion. What do I get? I'd be able to eliminate the one s-video cable going from my processor to my TV and one s-video going from my component sources to my processor. I'd also have to buy another component video cable (to go from processor to TV). Seems like a wash to me.
Besides, what do you do when you get your first source with DVI? And then the next one with DVI/HDCP? Face it, some video switching is nice, but I'm resigned to always having some sources run directly into the TV.