Full article at Slashdot
As of a little while ago (it is around 7:45 PM US Eastern on Mon 15 Sep 2003 as I write this), VeriSign added a wildcard A record to the .COM and .NET TLD DNS zones. The IP address returned is 64.94.110.11, which reverses to sitefinder.verisign.com. What that means in plain English is that most mis-typed domain names that would formerly have resulted in a helpful error message now results in a VeriSign advertising opportunity. For example, if my domain name was 'somecompany.com,' and somebody typed 'soemcompany.com' by mistake, they would get VeriSign's advertising.
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Some have pointed out that this will make an important anti-spam check impossible. A common anti-spam measure is to check and make sure the domain name of the sender really exists. (While this is easy to force, every little bit helps.) Since all .COM and .NET domain names now exist, that anti-spam check is useless.