I'm thinking of getting one for my mom as a birthday gift.  She has a Sony Bravia 40" HD tv so I'm not sure what the Wii would look like on it.  I know she's a little disappointed with standard definition television channels (she finds they look worse on it than on her older standard definition television).  Do the component cables I see advertised for them make any difference?  Thanks.

go to ign and look for what component cables to get for the HD tv

I use my wii on a 50'' HD tv. I also use component cables and it looks fine for me, as long as I'm not sitting too close or anything. Obviously not as good as a true HD picture, but not bad.

Component cables definitely make things crisper and more vivid.

You'll likely get jaggies on an LCD...but Bravias are good, and it probably won't be too bad.

I've played Wii on all sorts of TVs. It looks great on regular 30" or so SDTVs. It still looks fine on HDTVs though...a couple of my friends had certain AV systems that looked better than others...less jaggies on some TVs compared to others.

Nothing was that bad though...it's still super fun. I notice jaggies in Wii Sports, but most of us were too busy having fun to care.

You can find cheap Wii component cables for HD TV right here:

http://www.monoprice.com/products/product.asp?c_id=108&cp_id=10830&cs_id=1083001&p_id=3490&seq=1&format=2&style=

Also if you're looking for HDMI cables for the 360 Elite or PS3, don't get the ones from the store (usually very pricey) but get from this site and you'll save yourself a pretty penny.

You'd probably want the component cables for the Wii. I have a 60 inch Sony XBR2 and the Wii doesn't look that great running in 480i on composite cables (running in a 4:3 prospective and not stretched to 16:9 too). I had other problems too due to the size of the TV as well.

In all, (at least with composite cables) the Wii is better on SDTV's. 

I have a 32 inch widescreen 1080i/720p CRT HDTV ... The Wii looks pretty much exactly like a DVD and you don't really notice the lower resolution.

SDTV is usually 480i resolution and often has been highly compressed and is full of artifacts that are visible on large LCD HDTVs; the wii produces higher resolution and lacks the artifacts so it will (likely) not look nearly as bad as SDTV.

EDIT: I'm refering to analogue SDTV ... Digital SDTV (and a large portion of HDTV signals) are all in 480p and of similar quality as the Wii's digital signal.

 YES, if you ever need an HDMI cable, you can pick up HDMI cables on a site like www.newegg.com for $10 (~$15 after shipping) as opposed to a Monster brand cable at a place like Circuit City for $100. That's what I did for not only our PS3, but also the HD cable tv/DVR box which was a MUCH better deal. 

 I use a Wii on an HD TV. I tried to shield my eyes, but:

ZEE GOGGLES! ZEY DO NOTHING!

I'm running my Wii on a 50" Samsung Plasma

looks great, Zelda TP is amazing. And yes, I have the component cables.

Although my eyes are crap, so that might have something to do with the lack of jaggies =)