Only a couple of weeks ago we told you that Bing search results were now powering Yahoo! search results, now the next step in the Yahoo/Bing partnership has begun.

The transition of Yahoo! paid search campaigns to Microsoft adCenter began last week and is expected to be completed by the end of October 2010.

While the switch over is in progression advertisers will continue to manage separate accounts on adCenter (serving ads on Bing) and Yahoo! Search Marketing (serving ads on Yahoo! Search). However, after the transition is complete, advertisers will operate single account on Microsoft adCenter.

Yahoo says “During this period, you should expect traffic from your Yahoo! Search Marketing account to decrease, and increase in your adCenter account. But until this process is complete, you’ll still need to actively manage your Yahoo! Search Marketing account to have your ads displayed on Yahoo! and our partner sites.”

This change is expected to give the advertisers a competitive edge in their search advertising campaigns by enabling them to reach more than 159 million searchers in the U.S. and 15 million searchers in Canada on Yahoo! Search, Bing and their associated partners.

For existing advertisers with a Yahoo! Search Marketing account, there are three stages to complete the transition, which include:

1) Prepare your account for transition to adCenter
When you log into your Yahoo! Search Marketing account, you’ll automatically be taken to a new tab labeled “adCenter.” We recommend that you review your Compatibility Report, and fix incompatibilities between your current Yahoo! campaigns and the adCenter platform before starting the transition to adCenter.

2) Transition your account to adCenter
When you begin your transition, you’ll be able to create a new adCenter account, or indicate that you have an existing adCenter account that you want to continue to use. If you choose, you can use the transition tool to copy your Yahoo! Search Marketing campaigns over to adCenter. Please note that your campaigns will retain the same status (active or paused) as they have within your Yahoo! account, so you may start incurring click charges for Bing traffic right away.

3) Continue to manage your Yahoo! Search Marketing account
The last stage in the transition process will occur when Yahoo! Search ad serving moves to adCenter, which we expect to begin in mid-October and be completed by the end of October. During this period, you should expect traffic from your Yahoo! Search Marketing account to decrease, and increase in your adCenter account. But until this process is complete, you’ll still need to actively manage your Yahoo! Search Marketing account to have your ads displayed on Yahoo! and our partner sites.

As we have already mentioned, any ineedhits customers who currently advertiser with either Yahoo! or Bing via our Easy Search Advertising service, will not need to complete the transition themselves, you can leave that work to us.

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