I notice a lot of questions asked about HDMI vs Component. Anyone who uses HDMI cables understands HDMI is the best option if you want to get the most out of your PS3, visually. I recently bought HDMI cables because I'm new to this system. What got me looking into HDMI was something I noticed when I was playing the uncharted demo. Anyone still using component cables can try this and see for yourself. I would reccomend to any PS3 user to get HDMI cables if your TV supports it.
In the Uncharted demo, visit the first lagoon with the waterfall and stand in the middle. Spin the camera around Drake so you get the full motion blur effect and hold it. I did this because I figured if there was any way to test the limits of the system it would be something like this. I began to notice tearing at the top 1/3 of my screen every-time the camera panned by the waterfall. This was quite noticeable since the tearing caused the top 1/3 of the screen to be misaligned with the bottom 2/3rd. I just bought a new 40" samsung LCD so I thought maybe the PS3 just can't handle the visuals. But that thought faded quickly :P because of what I read about component cables. Since I was using component cables, I wasn't getting the fastest signal possible from my PS3 to TV. And I was right. The TV and the PS3 both can handle the game perfectly, but component will give you noticeable lag in certain situations. In part because how component splits your video signal into individual components for RGB and then has to re-combine the signal. HDMI gives you a faster, all in one digital signal that is superior over component. It was well worth it too since I spent $16.00 online for a good HDMI cable.
Examples: (note these were photoshoped to illustrate signal lag only)
Component: lag when motion blurred. notice the tearing across the top 1/3 of the screen.
HDMI: No lag when Motion Blurred