Contrary to what most people believe, an HDMI cable is not always better than a component cable. It is merely an alternative to it. It can be glitchy at times due to it being a fairly new technology. But for the most part, it works pretty well. It's great if you just want one cable going from your PS3 to your HDTV. No extra cables needed.

I personally use component cables because I have quite some distance between my PS3 and my TV. However, I also have to use an optical cable because of my 7.1 surround sound system.

My suggestion, pick whichever one is most convenient for you. Just check the back of your TV and make sure it supports HDMI first. Otherwise, find the link to the left and go after a good set of component cables.