mrguy - 3:48 pm on Sep 22, 2010 (gmt 0)

What happens to my Yahoo! account after it is moved to adCenter? Your Yahoo! accounts will remain open for an extended period of time. Following the transition to adCenter, you will continue to have access to the last 13 months of your Yahoo! Search Marketing account reporting and history. Eventually, your Yahoo! account will be closed.

About Yahoo! prepaid accounts Unlike Yahoo! Search Marketing, Microsoft adCenter does not require you to prepay your advertising costs before your ads appear. When you use the adCenter transition tool to move your Yahoo! account to adCenter before October 2010, you'll receive either a credit or a refund equal to the remainder of your Yahoo! prepaid balance, as follows: Balance of $25 or more: In November, your adCenter account will receive a credit. Balance of less than $25: In early 2011, you will be issued a refund.

Like I said, Yahoo itself is not going to be billing anything. The charges will come from Bing.