Skylights can be especially important if your kitchen doesn't have much window space. Letting some natural light in will make your kitchen more attractive, and save you money on lighting costs. Use fluorescents for general lighting. You can also achieve a nice 'wash' of light from fluorescent strips mounted to the tops of kitchen cabinets, if the cabinets don't go to the ceiling. Not only are fluorescent lights more energy-efficient, they also last much longer than incandescent lights.
Task lighting is even more important than general lighting in a kitchen.
Under-cabinet lights can focus light where you need it as you prepare food, cook and clean. Shallow under-cabinet fluorescent strips do a great job of providing this task light, efficiently and inexpensively. They can be hidden behind the lower frame of the cabinet, too, so that all you see is light. If you need light over a sink or counter surface that doesn't have a cabinet directly over it, recessed or droplights in the ceiling will focus the light where you need it. Again, opt for compact fluorescents, to save energy and ensure a long life for the light bulb.