Upon doing some research I now see I was still using the old Goto.com domain which has been on redirection to Overture.com since they switched names some time ago.
The reason it stopped resolving it seems is that amazingly Overture may have failed to renew their very valuable goto.com domain. It appears the name is no longer reg'd and a few days ago appears to have dropped from the zone file and subsequently stopped resolving.
I immidiately went to put a Snap on it but too late, someone beat me to it and may be getting a very valuable name, perhaps worth several hundred thousand dollars or more! If so this is really amazing, right?
Notice no owner is listed or reg and expiry dates, this is the complete Whois:
Domain Name: GOTO.COM
Registrar: DOMAIN BANK, INC.
Whois Server: rs.domainbank.net
Referral URL:
http://www.domainbank.net
Name Server: NS1.OVERTURE.COM
Name Server: NS2.OVERTURE.COM
Updated Date: 15-jan-2003