There's a really obvious reason why a great many people spend a great deal of money creating their kitchen and that is because for most people these days the kitchen in no longer simply a place for preparing food but has evolved to become the hub of the home. It's also a space that gets a great deal of use both during day and night times so it's really worth getting the lighting just right.
Modern kitchen lighting is light years (excuse the pun) away from the harsh fluorescent strip lights once seemingly ubiquitous in kitchens. These days you can choose from low-voltage, recessed spots and track lighting, dimmer controlled wall sconces, elegant pendants and LED's in every form imaginable. The problem now is not lack of choice but deciding from the bewildering choice available what works best for your situation.
A noticeable aspect of good kitchen lighting design is the way it operates on different levels to mirror the way that kitchens themselves often serve many purposes. This is typically accomplished by grouping lighting into distinct types (ambient, task and mood) and then blending these groups to achieve different effects.
The category termed mood lighting comprises aspects of what lighting designers often also call accent, feature and/or decorative lighting. Regardless, the basic principle is very simply to assign each of the main groups a separate circuit, preferably controlled with its own dimmer switch so as to be able to alter the relative balance between the lighting groups.
Ambient light works best when it is most unobtrusive. Its purpose is to suffuse a space with a soft, overall background glow and let the more interesting lights assume centre stage. Low-voltage 12v recessed halogen spots (or more popularly these days, LED spotlights) are perfect for this. High brightness, warm white retrofit LED replacements are now making the financial case for replacing halogen spotlights with LED equivalents totally compelling.
Eventually of course the business of preparing food comes into play and with it the issue of effective task lighting. The layout of most kitchens is such that working surfaces are never properly illuminated by even the best ambient lighting (basically you always create your own shadows). The most common solution is to simply place LED or other low-voltage lights beneath wall units so as to cast light directly on the work surface and not spill over elsewhere.
Mood lighting is just a fancy term for creating whatever types of ambience you want for your kitchen. Examples include angled up-lighters concealed above wall units, spot lights to accent particular features, eye-catching pendants dropping over a dining area or low-heat low-voltage LED lights set into glass fronted wall cabinets or a plinth or kick-board even.
LEDs and kitchen lighting are practically an entire topic unto themselves. They produce hardly any heat, cost very little to run, are highly durable and lightweight, and endlessly versatile. LED lights can be used for task, ambient and mood lighting situations and are already supplanting more conventional kitchen lights thanks in part to the ease with they can be retrofitted into existing fixtures.