Get a lighting designer involved. In your situation, the correct artificial light is imperative. Most lighting stores will have a LD on staff and whose services are free if you purchase their products.

I am going through this same debate in my head and keep wondering if it will look too dark as well, but have decided to go for it. GreenDesign's suggestion is a good one. Even with a skylight, you have to figure that you will be relying on artificial lighting the majority of the time anyway. A good mix of recessed lighting, pendant lighting and cabinet lighting will hopefully keep it from looking like a cave and instead provide the warmth and elegance that I think dark cabinetry can provide (that is what I keep telling myself anyway). Maybe add in some glass front doors to to break up the cabinets as well, be sure to use a lighter countertop and backsplash. I have been pouring over design pics and websites trying to decide between white or dark and have seen many lovely kitchens that have eased my concerns. If I knew how to imbed images, I would provide you lots of examples!

We are doing dark stain perimeter cabinets with a medium stain island. The medium stain island has dark highlights to tie in with the perimeters. We are also doing dark countertops. To break up the darkness we are doing a light tumbled travertine backsplash (2x4 brick). We have a skylight over the island, a window over the sink, and windows in the breakfast nook, and french doors with windows close by. Then we have recessed lighting, soffit lighting, undercabinet lighting, pendants over the peninsula, and a light fixture in the breakfast nook. So we have many different lighting options with some lights on dimmers. HTH. Good luck!

Here's a GW thread on dark cabs. Also do a search for Kitchenaddict's kitchen on GW, she has a beautiful kitchen with dark cabs, light countertop, and tumbled crema marfil backsplash.

Here is a link that might be useful: GW dark cabs thread

Just realized kitchenaddict's kitchen is in the thread I mentioned above.