Blizzard recently changed their add-on development policy, and it affected quite a few developers. An initial compliancy date was set, however after some feedback from developers, Blizzard has granted an extension.
On March 20, we released the new add-on development policy to the public as an ongoing effort to help ensure add-on integrity, safety, and quality for the community. Since that time we have been in touch with many UI development communities on what the policy means to them and the continuing development of these add-ons. We would like to announce further that we are providing a sixty-day grace period beginning at the time of the initial release of the policy for UI developers to comply with the new policy. After May 19th, Blizzard Entertainment will begin to enforce the Add-on Development policy, and developers found to be in violation of this policy will be contacted directly.
You can find the whole forum thread here.