which programs with more functionality/hardware support etc? XBMC supports linux/osx/windows, has support for tons of streaming protocols including things like encrypted rtmp. includes about 3 different vendors/os hardware video acceleration. has an api for communication. includes powerful scripting using python. has a new addon system for easy installation of extras... i can go on
I don't think there is anything even close to it personally. the point of xbmc originally was to have a decent media player. the point wasnt that it was running on a games console. that part was just the means, due to the availability and capabilities of the xbox. of course it makes it easier to develop when the hardware /os is the same, so there is some advantages to that also.
the interface behind xbmc has been copied and replicated on many software devices now, so it just shows that they must have got it right. even the new amiga media center looks like xbmc (albeit with a crap skin (sorry) and 1% of the features).