I am posting answer from owner of estibot.
He don't have platinum acct
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Ah, OK they were referring to type-in domains.
The answer is still the same - Estibot shows primarily U.S. data for searches. Actually the differences in the domains they were referring to are just due to normal variation over time. Official overture data is from Jan 2007, but Estibot data is collected over a longer period of time and there are differences.
The original poster tested just a few domains and drew fast conclusions, but if you look at thousands of type-in domains (easy with the estibot type-in traffic tool) you'll see that the variation goes both ways. For instance, espn.go.com score is higher on Estibot than on "official" overture.
The Estibot data however is not limited to US data - when US data is not available, estibot will display, when possible, other relevant data such as UK (see thesun.co,uk, o2.co.uk), Australian or other available data.
As for which data is better - there is no answer to that - overture data is not up-to-date regardless of the source you get it from, but the vast majority of it is still meaningful data for domain research.
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I believe estibot is displaying european overture numbers for a region or particular country.
They are drastically off for generic domains.
4,659 - Tennis.com (u.s. overture)
1,905 - Tennis.com (estibot)
612 - usstove.com (u.s. overture)
114 - usstove.com (estibot)
I checked 6 different ones, same experience.
And, americanized domains had u.s. overture numbers but with estibot they showed nothing.
