About a year ago, Apple told its MobileMe customers that the company would discontinue the service and transition customers to a new service called iCloud. The deadline for most customers is June 30. Customers who purchased additional MobileMe storage will get a few extra months to apply for a free iCloud expansion upgrade.
On Apple's MobileMe transition page, there are several other dates mentioned. The first is one for using MobileMe email addresses on noncompliant devices.
What if I just want to keep using my email on all my devices?
As of May 1, you can choose to keep using your mail after MobileMe ends, even on devices that don’t meet the iCloud system requirements. Just go to me.com/move and select the option to keep using your email after MobileMe ends. Once you have completed this short process, your mail will continue to work on devices that don’t meet the iCloud requirements after MobileMe ends on June 30th, 2012.
Another date is for those customers who purchased additional storage on MobileMe. They have until Sept. 30, 2012 to apply for a free upgrade on iCloud.
I currently have more than 5GB of storage for MobileMe. Will I be able to move to iCloud?
Yes. The free 5GB of storage provided by iCloud is used only for Mail, Documents & Data, and Backup. Purchased music, apps, books, TV shows, and movies do not count against this 5GB of storage, nor do the photos in Photo Stream. As a result, most users will not need more than the free 5GB of storage after they move to iCloud.
MobileMe members with 20GB of purchased storage receive a complimentary iCloud storage upgrade of 20GB, and accounts with additional purchased storage (40GB to 60GB) receive a complimentary upgrade of 50GB after moving to iCloud. These free upgrades are good through September 30th, 2012. After that date, you can continue the upgrade at the regular price or let it expire and use the free 5GB plan.
Another interesting transition item that many might have overlooked is the refund for unused activation codes, which is also June 30. So, if you have a MobileMe box that you never got around to installing, you can get a refund here.