GoogleGuy comments on a new Google feature. If you search for a domain in the form "whois:domain.com", Google will display a link at the top to a web site displaying the whois information for that domain.
Update: It seems that Google has turned off this feature, as the whois sites listed were infringing on the policies of netsol.
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I think we just link to a site that does whois, which is what FAST does too last time I checked. Querying whois ourself would be a much larger undertaking, but if anyone has recommendations for a good whois site to point to, feel free to suggest it to webmaster [at] google.com and just say "pass this on to GoogleGuy" or something. I think webmasters notice the whois more, but at the same time we added several other things like package tracking for the US postal service:
It's just part of trying to make sure users can type stuff into the search box and get useful results..