Nasty reports are beginning to surface that the latest Wii update, which was intended primarily to remove "homebrew" content, is actually destroying some consoles.
Both NeoGAF and and Nintendo's technical support forum are being hit with reports from people whose Wii consoles have frozen during the download of the 4.2 update and will not reboot when they're unplugged and restarted. It was originally suspected that only consoles with the Homebrew Channel installed were being damaged but it now appears to be a random issue, as some "non-HBC" Wii owners are claiming that their systems have been "bricked" as well.
The problem appears to lie with the "boot2" program, which the Wii requires to start up properly. Changes to that program as a result of the update leave it prone to write errors which can cause the console to refuse to boot, regardless of whether or not it has ever been modified. The risk is only present during the update process, however; once the update is complete, there is no risk of your system coming to harm.
Nintendo has remained silent on the matter thus far and some users with out-of-warranty systems have reportedly been told they'll have to cover the cost of repairs themselves, although that stance could presumably change if this grows into a "Red Ring of Death" style problem. In the meantime, until the matter is settled once and for all, it's probably best to just avoid this update altogether.
via: Nintendo Everything