What if the technology existed for someone to intercept all telephone calls in an exchange not owned by anyone else? My phone number is 410-309-6910 (6911 is fax). Suppose no one actually owns 6912 and 6919. If someone misdials my number they'll get someone else. Maybe that someone will have a recording that says simply "Press '1' to send a fax. Press '2' to talk to an attendant." What is the harm? Faxes meant for me could be easily misdirected. Calls intended for me could be answered by someone who might redirect business to a competitor. I lose the potential client. The potential client loses me. Maybe.
Check it out. Click on www.avolio.cm. (Note, "com" is misspelled.) You get an error (or redirected to the correct address... hmmmm.) Now, Click on www.aviolo.com. My domain name is misspelled. But Verisign "owns" .com, and so helpfully intercepts it. Not as bad as whitehouse.com instead of whitehouse.gov. (And I purposely do not include the links... the ".com" address
The main problem – from a security perspective, anyway – is that DNS information (the Domain Name System, among other services, translates www.avolio.com to its actual IP address, for example) is expected to be accurate. E-mail servers, such as mine, depend on getting a response of "no such name" to make antispam decisions. Again, think of the above telephone allegory. E-mail directed to me should get to me. E-mail directed to firstname.lastname@example.org should, for now, bounce. What if someone claimed to be the mail server for "*.com?" That is effectively what Verisign is doing for .com and .net.
DNS depends on correct DNS responses, not responses geared to make the life of web surfers easier.