When you shop around for top paying keywords, you will find yourself faced with such list providers who sell data based on Overture's bid estimates. They think that if the bids are high in Overture then they must be in Google, too, and they leave it at that. Most likely they do this because the learning of Overture's bid tool is much easier to get at and understand than Google's.
But things are not that straightforward. Not only that, but such naive thinking can end up costing you a lot in terms of AdSense revenues plus or minus.
Let's look at an example to see how these two services really compare.
Keyword Phrase Overture Top Bid Google Average Top Bid
settlement funding $100.00 $22.96
business dsl $9.00 $6.37
home equity line $7.84 $20.37
Now if you were going to choose the best top paying keyword
phrase from this list, which one would you pick?
Going by Overture's bids, 'settlement funding' would be the clear winner. But once you ran AdSense ads for this phrase, your results would be quite disappointing. After all, the top paying advertiser is spending no more than $22.96 in Google's system - the one that powers AdSense!
To make matters worse, if you saw these words in a large list of top paying keywords that went strictly by Overture's bids, you would end up 'leaving money on the table', since you would miss out on targeting high paying term like 'home equity line'.
According to Google, these keywords are a lot more profitable than what Overture shows them to be.
So, you should go by Google's results, not Overture's, if you want to have a more accurate picture for your top bid estimates. So, if you are familiar with how to get bid estimates from Google's traffic estimator, then be sure to also check the bid prices for exact matches (e.g., [home equity line]),since exact matches tend to be higher in price than the other match types, and they are often used in AdSense.