I am sure that most you saw the screen shot of Local OneBox test that Paul Jahn posted at searchengineguide.com (and was discussed by Greg Sterling) which shows the OneBox with 10 listings instead of the current 3:

There are several points of interest in the test.

•The space allocated at the top of the page is only about 1/3 more than currently allocated with the 3 listings.

•This is done by having less information and fewer links for each listing. They may also be using a smaller type face.

•The new result also adds 14 additional links into Maps. I had wondered recently, how much more traffic Google could send to Maps by adjusting links, obviously a lot more if they want to.

•It is also of interest that the reviews are emphasized as opposed to directions in the current OneBox.

It has never made too much sense to me to only highlight 3 local listings in the OneBox. Why 3 instead of 5, 7 or 11? The question for Google is: do the top 10 local listings provide more relevancy than 3 local + the organic results. My inclination is to say yes as my perception is that Google’s local results have improved over the past year.

The question for the business owner is why 3? Why should some businesses be rewarded and not others? Why not mine? Will the number vary by geography or industry?

I am glad to see Google testing this as there is no good reason for just 3. Determining the “right” number is another question altogether. At some point their value to the business owner though is diluted by the quantity and the viewer may be distracted as well.