For instance - if I'm on holiday I shoot RAW + JPG and almost always use the jpg only. I have the RAW files if there's a particularly good shot I want to process and keep, but mostly the JPG's are good enough.
When I take pictures of bands at gigs I don't do much post processing and I only need relatively small files when I'm done so I use JPG's and don't even bother with RAW files. For images I put on a website and ones which will never be enlarged above A4 I don't mind processing a copy of the original JPG as the result is always more than enough in terms of quality and file size.
When I take portraits I shoot in RAW as all files that make the grade get processed to some degree. I only bother shooting RAW + JPG for portraits when I want to show instantly on a laptop at the time of creation, but this is rare.
To sum up, shooting RAW + JPG is a good standard to adopt as you will always have the RAW files and an instant JPG which should be good enough for most uses if you are competant with your camera. Hope this helps but do remember that this is just my opinion...