Apple has posted a guide to help users transition from MobileMe to iCloud. The good news? Just like TiPb's been telling you from the start, there will be web apps for Mail, Calendar, Contacts, and Find my iPhone. Also, if you need more storage, you'll be able to buy it. The bad news? iWeb, MobileMe Gallery, and iDisk are toast.
iWeb, Gallery, and iDisk users are encouraged to move their data off MobileMe before the June 30, 2012 cut off date, and knowledge base articles have been posted to give additional information.
What about those of us who have a plethora of Apple IDs? (iTunes, MobileMe, developer, discussion, etc.), will Apple finally let us bring them together, and in the cloud, bind them? Not so much...
If I use different accounts for iTunes and MobileMe, can I merge them into a single account and use it with iCloud? No. You cannot merge two accounts into one. However, you will be able to move your MobileMe account (firstname.lastname@example.org) to iCloud and, if you choose, you can continue to use a different iTunes account for store purchases and iTunes in the Cloud.
Family pack users can, however, move to separate iCloud accounts.
Check out the full transition guide via the link below, and let us know if it answered your questions, and if the answers are the ones you wanted.