Interestingly enough, it's easier to find RAW in dSLRs now than TIFF, eventhough RAW is supposed to be more powerful (My Nikon D50 has RAW (NEF; Nikon's version of it), but TIFF appears in the D200 which is double the price, not sure about D40 or D80 of the top of my head).
Personally, I'd rather have TIFF. It's a more universal format and like RAW can be lossless. The problem with RAW is that each manufacturer has it's own version of it and in my case, Photoshop doesn't even support Nikon's NEF. So it introduces yet another step in the workflow (since Photoshop can't open NEF, it means I can't create actions that can batch process the files for me, such as batch changing the white balance - which is what you'd want RAW for to start with).
Also, I prefer to get my pictures as good as possible in camera to start with.
Another feature to look out for is if you can use a different colorspace besides sRGB, which is used by most cameras. Usually the alternative on higher end cameras is Adobe RGB (1998) (or varients of it). The difference is subtle, but will result in more vibrant prints and more leniency towards manipulation and enhancement.