Before 9:00 am on Thursday, July 10, Italian time, it will be done step by. Mac to MobileMe. This was announced Apple is the same with a notice for current users of the service. Mac that will suffer a blackout of service due to the transition between 3:00 and 9:00 Thursday: In this window you can not access the services , With the exception of the mailbox through client:

Mobile Me Launch
7/9/2008, 12am-6pm PT

As part of the Mobile Me launch, will be taken off line at 6pm PT on Wednesday, July 9th. Members will be unable to access or Mac services during this time with the exception of. Mac Mail accessed via a desktop application, phone, pod or touch.

mobile me will be available as soon as possible during this maintenance window. In the same hours should be available to download iTunes 7.7.