As Danny reported over the weekend, Google added a significant search feature (Matt Cutts mentioned it first to let us know). You can now type into Google, whois domain.com and get the whois information for that domain.
For example, whois seroundtable.com returns this result:
When you click on the whois link, you are taken to Domain Tools. Domain Tools is one of the most widely used whois databases out there. Curious if it was a formal partnership or just because Google likes the resource? In any event, the Sphinn thread has one comment about that:
I can't believe that they have "partnered" with a site the does an SEO analysis upon clicking? http://www.domaintools.com/seo-score/
Forum discussion at Sphinn and DigitalPoint Forums.