According to Artik of French site Logic-sunrise.com, the Nintendo Wii 2 is allegedly set to arrive in 2010 and include Blu-ray and 1080p support.
This rumor appears to stem from an internal source of the marketing department at Nintendo France, however, little information is available to substantiate it unfortunately.
To quote from Ripten (linked above): "It could be that it wasn’t posted on the French site itself although that wouldn’t make much sense.
All in all, the rumored “leak” states that Nintendo is working on a Wii sequel with the following:
• The Wii2 system will feature a Blu-Ray drive with a secondary aim of stopping piracy.
• 1080P and lower resolutions will be supported, for blu-ray movies and games.
• The release date is scheduled for third quarter of 2010.
• The release will be worldwide and on the same day for all countries.
• A scheme will be available in which it is possible to trade in the original Wii for a cheaper price on the new Wii 2."