If you don't believe it, try the commands for yourself:
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overmind% nslookup
Default Server: localhost
Address: 127.0.0.1
> set querytype=a
> www.google.com
Server: localhost
Address: 127.0.0.1
Non-authoritative answer:
Name: www.l.google.com
Addresses: 74.125.53.147, 74.125.53.104, 74.125.53.99, 74.125.53.103
Aliases: www.google.com
> server 208.67.220.220
Default Server: resolver2.opendns.com
Address: 208.67.220.220
> www.google.com
Server: resolver2.opendns.com
Address: 208.67.220.220
Non-authoritative answer:
Name: google.navigation.opendns.com
Addresses: 208.69.36.230, 208.69.36.231
Aliases: www.google.com
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Talking to my local DNS server, www.google.com resolved to IP addresses in the 74.125.0.0/16 netblock, which is assigned to Google.
Talking to resolver2.opendns.com, www.google.com resolved to 208.69.36.230 and 208.69.36.231, which have no reverse information, but are in the 208.69.32.0/21 netblock which is assigned to OpenDNS.