Another bug mentioned was one resident in Spaces that would disallow users from assigning apps to a Space via drag-and-drop. Apple requests that developers evaluate the update thoroughly, since it includes modifications to code for almost two dozen core services, such as iLife, networking services, iChat, and Mail, among others. MobileMe – Apple's replacement for .Mac – will launch on July 11th, and requires the 10.5.4 update, placing the release date for the patch some time between now and then.