Wow, very quick & comprehensive answer, mweerden, Thanks!
I see about the "colors off"-issue, but I'm not sure I "have the materials" and I definitely lack "the experience" (didn't even know what DNG was until a week ago, lol). Let's see...
Just one follow-up:
You apparently have and maybe use the 870 IS yourself, right? So you don't shoot your images in DNG but in CHDK RAW? I mean, I'd do that myself if that means that the colors are not distorted, but I understood that that would need at least one extra step until I can get the images into Aperture; i.e. another software that I'd need to load the images from my card to before I could then again put them into Aperture. That is to say: It's more tedious (at the moment, I just load the DNGs from the card straight into Aperture, which is kind of hassle-free).
What solution do you use to do this? DNG4PS2 doesn't seem to support the 870 IS (cf
http://code.google.com/p/dng4ps2/). Is RawTherapee (
http://rawtherapee.com) the program of choice?