Update to the SSBB errors, dirt is the cause.

[MaxwellGT2000]

 In Short:

Nintendo released an annoucement that the SSBB errors people are getting is due to dirt and smoke getting into the system and getting on the lens. (One more reason for you smokers to stop XD)  SSBB is the first game to use dual layer DVD which needs the lens to be clean.  They said if you get the error they will clean the system for you free of charge, including shipping, etc. though this is only in Japan I'm sure it would apply here if the same thing happens.

The Article: 
Yesterday's report of a buggy firmware update procedure for Japanese Smash Bros. Brawl discs was apparently just the start of problems for Nintendo. Today, the company issued a statement about reported disc read errors for the game.

According to the statement, Nintendo has received complaints from Smash Bros. Brawl buyers of the Wii being unable to read their newly bought disc, or of videos chopping up during playback. These users claim to have had no such problems with past games.

Nintendo has come to the conclusion that the problem has to do with dust and tobacco building up on Wii laser units. This effects Smash Bros. Brawl while leaving other titles unaffected because the new fighter uses a dual layer DVD, which is apparently more sensitive to a dirty lens.

The problem can be fixed by simply cleaning the Wii drive lens. This is something that the masses are apparently incapable of doing, so the Nintendo has decided to clean Wii units that are sent to them, free of charge.

Those who need this service for their Japanese Wii will have to send their system, warranty card, and copy of Smash Bros. Brawl to a Nintendo service center in Kyoto. Nintendo will be paying for the shipping, so there's no loss for consumers, except for a one week period without Wii.

For more details, Japan-based readers should check out Nintendo's Smash Bros. error page.

This announcement applies only to the Japanese market.

The Link:

http://wii.ign.com/articles/849/849072p1.html