B&W announces the i-Command wireless LAN based home theater control system.

The i-Command system is a patent-pending technology that works through standard Ethernet networking to control home audio and video components, multiroom media systems, lighting, projectors, screens, motorized drapes, peripherals, and more, eliminating the clutter of multiple remote controls, expensive wiring, and complex programming.

A component called i-Node needs to be connected to the RS-232 port of the hometheater unit (mostly high-end units have that port). If this port is not available the i-Command system also has iR based control units. All compenents can then be controlled from a PC, PDA or the i-Command Touch panel.
Its not a low-cost solution. One i-Node costs $300.
More details at the i-Command site.