First of all, while the statement that RAW is losslessly compressed while JPEG is lossy compressed is in general true, it is, in the case of the D70, false. The D70 actually uses a lossy compression on the RAW files.
Secondly, I constantly hear that working with the RAW files makes for a slower workflow than working with JPEG. While I have seen this to be true for some people, for me, it's very much the other way around. The majority of my time is spent ranking, sorting, and selecting. Once I have culled out just the selects, there's very little time spent correcting images. However, I find that in general, I can make good looking corrections faster to a RAW file in ACR than I can to a JPEG in PS.
Of great importance to those of you shooting for catalog work, accurate color can also be had more easily from RAW. ACR allows for saved Calibration settings for each camera you own. I have found that all of the cameras I've owned have differed at least somewhat from accurate. Using a ColorChecker chart, I can make all my cameras 1) match each other and 2) match reality allowing me to deliver perfectly matched color from every camera I own without having to add multiple Adjustment Layers in PS.
Finally, I shoot RAW because it allows me to change my mind later. The people who know exactly what they want, exactly how to get it, never make a bad judgemt call, never get fumble-fingers, and always make perfect images amaze me. I am not one of them. I often want a 1/4 stop different exposure, 50K differnt color temperature, or different sharpening after I arrive home. I find that RAW facillitates this MUCH better than JPEG. With JPEG, I feel I am much more locked into the image as shot if I want to deliver a final file with the highest possible quality.
A typical shoot for me is somewhere around 500 images. If I have the time to sit down and do it in one shot, 60 to 90 minutes are sufficient to sort, rank, apply metadata (copyright, location, description, keywords), correct, resize, and create a web gallery of the shoot. Of that time somewhere around 10-15% of that time is spent on the corrections. The I spend the OVERWHELMING amount of time sorting and selecting. Mayebe I just can't make up my mind. [img]/ubbthreads/images/graemlins/smile.gif[/img] It just doesn't slow me down at all to use RAW and once in a while it'll speed things up because the corrections are easier.