The connections might be the same but the wire is not. The audio (red and white) cables are not rated as high as the video (yellow) cable. I have heard some say you could use three video cables but I wouldn't recommend that.

Several good, inexpensive component cables have been recommended here.

I use this:

GE AV92675 Ultra Prograde Digital Component Cable (12 ft)

Good stuff.

I got a new tv coming tomorrow that has component inputs. I just picked up some at Target to try out (GE's I think, $12.95 for 6ft).

I'm one that does believe cable matters. However, I do think it is subtle. I agree with others there is a ton of stuff that makes a difference in quality of video (and audio). I'll use these GE's as I check out the new TV. I'll also get get some nice cable to compare. More of a Kimber cable guy myself, tho I don't know if they have component wires. I've been using their speaker wire for years
http://www.kimber.com/

I'm obviously not an expert, but it seems to me with regards to cable, we get into diminishing returns. The 30$ Acoustic Research cables are probably at least half again as good as the 8-12$ Target/WalMart cables; so that is worth it. But the 80$ Monster cables are not 2x as good as AR; from research and reading opinions, I'd say they're maybe 2-10% better on an 'average' consumer setup [ie, not a 20000$ TV], if that much [and of course calibration and proper setup goes a long way.] I've got AR optical cable and component cables, and have never had a problem. Sound through my HT sounds great, and picture on my TV is very crisp and detailed [although I do need to calibrate it, we just got it installed.]
But a lot of it is perception; maybe if I saw Monster vs. AR right next to each other, on equivalent setups, I'd say Wow, monster is better. Or I might say, Well, Monster appears a little better, but only because I'm looking for it.
To echo what other people say; do the research [which you are], buy what your wallet will let you buy, don't get snowed by salespeople who push you toward the highest price/profit items, and keep your receipts. Maybe buy them both, try them both, keep whichever one looks better to you. If you spend 300$ on cables, and you sit there and say Man this is a great picture, then it's worth it.

I've just ordered the AR pro series component cable from accessories4less.com for my 47in RPTV. I have a pro series optical cable, and have been impressed with the sound and build quality. It looks better than the cheaper ones found at Best Buy. It should arrive today, so I can give it a shot tomorrow maybe. It was $27.99 I think.