I use CF for RAW and SD for large JPG. When I review my shots I find the JPGs are almost always excellent for what I wanted. If so I never use the RAW. The JPGS in the D800 are amazing. Also I can use the SD card directly in my laptop computer.
Over the years I always used RAW with the D100 but then with my D2Hs I found the JPGS were often great. Then with my D700 they kept improving. Now with the D800 and good settings on the camera the JPGS are great. So I find now I hardly ever look at the NEFS on the CF card. (they are just nice to have there in case).