The official site for Wii Chess is now online, offering a short trailer and some small screenshots. Some features described include:

• One player mode - Face off against state of the art Artificial Intelligence, with an adjustable difficulty setting suitable for n00bs and grandmasters alike.
• Online multiplayer - Challenge other players from around Europe through Nintendo's Wi-Fi Connection.
• Motion - Move your pieces by holding the Wiimote vertically and using the +Control pad and A & B buttons.
• Customization - Pimp your board and pieces in a variety of styles.
• Helping hand - Beginner players can choose to have an on-screen prompt showing where pieces are allowed to be moved.
• Rewind - Relive your finest victories (or worst thrashings) using the record and replay features.

Sounds like this might be limited to Europe. I still think it's a perfect candidate for WiiWare and not a full blown release. I doubt it's very big in terms of storage space, and it would save swapping out discs each time you want to play it. I'm getting lazy in my old age, lulz.

Here's that trailer: