Yahoo and Microsoft have provided an update on advertisers’ transition to adCenter as the Search Alliance gets underway.

Yahoo advertisers will soon either have to create a new adCenter account or link their Yahoo account to an existing adCenter account. Later this month, Yahoo advertisers will see an "adCenter" tab in their Yahoo Search Marketing account. This will take advertisers to the beginning of the account transition process where they’ll be walked through the steps.

"Once you create your adCenter account, it will be active and your ads will be eligible to serve on Bing right away," Yahoo says. "As a result, you’ll be managing both your new adCenter account and your existing Yahoo! Search Marketing account in parallel until ad serving for Yahoo! traffic transitions to adCenter, so plan to budget accordingly."

Advertisers will need to download Silverlight to look at the differences between their Yahoo and adCenter accounts.

As far as organic search results, Yahoo says Bing will start powering Yahoo results in late August. Yahoo will email a confirmation to advertisers once the adCenter tab becomes available and once the organic search transition is complete.