Hi R. Dixon,
If you have an image where the dynamic range is wider than what the JPEG format can support, then there is the potential for loss. JPEG is a compression algorithm - well several of them - applied to image-information to save on file-sizes.
Not all pictures necessarily exceeds the JPEG format and for many of those who do, it;s not visible to the naked eye and certainly not even visible on a computer monitor.
RAW files gives you somewhat more leeway to push post-processing further without getting an overprocessed look. For example: shadow detail in a high-contrast exposure can be lightened and more detail be pulled out of the shadows than a JPEG - most of the time. But it's not exactly HDR-technique either, so don't expect miracles.
Finally, gradations can sometimes be handled more elegantly with a RAW file. It depends a lot on what else is in the picture - JPEG may cover it, but it may not.
Ultimately you should make this decision for yourself. My suggestion is that for everyday shooting just stick with JPEG - good pictures are good pictures and they look fabulous in 18X12 inch prints. Don't worry - you do not need to have that feeling when you have taken a great shot that you really like - but in JPEG - that "OH DRATS! now it's gonna suck on a big print because I didn't use RAW".
Experiement. If you go out in the "golden hours" of the day with your tripod and shoot some killer sunsets, foliage, mountain and water shots - try it with RAW. Just a few to begin with. Then process them with RAW software and see if there is a significant difference to your eyes - but don't expect a "HEUREKA" experience looking at your monitor (unless you got some 30 inch Lacie OLED beast for $5.000 dollars..lol). And see where it gets you.
RAW files are large and RAW processing is an extra step in the work flow.
Not that it has any bearing on what's right for you, but I only shoot JPEG.
Cheers
