Actually some TVs support 1080p via component and some don't. But purely per cable specifications you can get 1080p with component.
People shouldn't have a reason to use composite though, if their research is true then it's purely because by including composite cables by default uninformed people never try anything else. Fancy inputs or not you must have a really old tv (and by that I mean truly old) to not have at least S-Video, and later on component.
Unless you're in Europe and have an old TV, then you'd have scart (which sucks compared to component but due to being drool-proof stayed really strong in Europe for ages).
As for me I'm using HDMI on the PS3, HDMI from my computer and component on xbox360, ps2 and Wii. Used to have PS3 on component too, but it doesn't upscale ps2 games with it. Would have the xbox with HDMI but there are no more HDMI inputs on the tv and I already had a component switcher (and I nicked the component that came with my brother's elite).







