I always find it depressing when I take a picture by moonlight and it ends up looking very much like a picture taken by sunlight, as opposed to looking like the scene looks to our eyes. Always have to keep in mind that a CCD != rods and cones.
Sensitivity is nice but as far as I'm concerned, dynamic range is the main thing that's needed in digital photography. DSLR sensors have gotten much, much better over the last 10 years but there's still plenty of room for improvement.