Diana,
there are advantages and disadvantages to each approach. Some folks on this forum shoot jpegs exclusively -- Julie Poole for example -- and her images are outstanding. So the question is more "what are you going to do with the images" than whether RAW or jpeg is better.

In a typical workflow, you open the images for initial viewing, select the ones you want to keep and/or edit and then resave them to a separate folder. Then you open them again, edit and enhance them, and save them probably to another folder. When you print them yourself or have them printed, you open and close those images again. Each time you do it, the image is degraded to some extent. You can avoid that issue to some extent by saving the edited final version as a .tif file which is your archive copy. That way whenever you need that image for printing, posting, etc., you simply open the .tif and resave it as a jpeg to send to your printer or posting host computer. That last jpeg is virtually as good as your archived .tif.

In RAW, you save the original RAW image once you've made your initial cull and it is a file that has received no processing at all. Which means that as software technology improves and allows us to get more detail out of our original RAW files, you'll be able to do so. I have RAW files that I took with my D30 (not 30D, the original Canon prosumer camera) and when I process them in PhotoShop CS4, those images look as good as anything coming out of a current DSLR -- except they are only 3.4 mpx.

In RAW, my workflow is to review all the RAW images in Bridge and select the files I want to work on. I save those in a separate folder as tiffs. Once they are all edited and finalized, I resave the tiffs into my Final folder. When I send them out for proofs, I open them, save them as jpegs and send them to the lab. When I post them to my website, I open them, resave them as smaller jpegs or gifs and save them to a separate folder. My original RAW files are archived and I have the final edited version saved in a non-destructive file format for use whenever I need them.

As Geo says, shooting RAW adds complexity to the workflow and eats up storage space. But, for me, it provides a long-term flexibility that I don't get with jpegs and it allows me to retain the original image quality for as long as I store the RAW files. That's important to me. I have folks calling me virtually every month asking for a print of an image I took at a dog show 5 years ago. The prints I make today with those files are better than the prints I made 5 years ago.

One additional advantage of RAW is the ability to correct for color-casts very easily in the initial edit in Adobe Camera Raw. The images you just took of the cats with the slightly magenta background tinge would be corrected with one click in ACR.

Hope all this stuff helps.

Jim