For those remodeling and looking for an "open" feel where perhaps the wall or half wall separating the kitchen and the dining room is taken down, a strategically placed island acts as a subtle room divider mentally separating the kitchen from the dining room but with a much more open feel.
In addition to seating 4 (or more), islands today are used to house "luxury" appliances that do not fit in the cabinet structure like a second microwave, second oven, wine refrigerator or even another cooktop. Islands many times are fully wired for electricity and have plumbing for a second sink. The base of an island can be used as a wine rack. The possibilities are almost endless.
Maximize natural light by having windows and skylights, and keep kitchen wall surfaces light in color to reflect daylight. Custom kitchen islands work great by using pendant or recessed fixtures to direct light onto the kitchen island and other work areas. Electrical codes will likely require that electrical outlets be located on the sides of fixed kitchen islands, not on the top, to prevent electrical shock.
Islands can "float" as well. Smaller islands used primarily as an aid in cooking or baking can be fitted with wheels and moved around the kitchen as needed to aid in cooking. Whether you consider a floating island will probably depend on what you have installed on the floor now, or plan to install (a soft wood will be nicked and scratched).
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