Why ask here before actually attempting to sign up? If you went to register you would see its open worldwide duh.
Humm jabb, thank you but I already tried to register, that's why I am posting. I had a problem when signing up. While every country are listed in the form, I couldn't sign up. It always return to US.
This is the reply I got from Adcenter support: Microsoft adCenter is available to advertisers around the world. Currently we have live markets available in the U.S., the U.K., Canada, France and Singapore. Even though we do not have markets in every country worldwide, customers can select any market they wish their ads to serve on.