Apple's iCloud FAQ Spells Out Web Apps, Death Of MobileMe
The FAQ centers mostly around the death of MobileMe and the transition to iCloud, but it does shed a bit of light on how iCloud will be established in due time. For starters -- if you had an active MobileMe account as of June 6, 2011, your service has been extended through June 30, 2012, at no additional charge. After that date, the MobileMe service will no longer be available. Mail, Contacts, Calendar, Bookmarks, Find my iPhone and Back To My Mac are all going to be made available in iCloud and through icloud.com (from any computer with a web browser), while iWeb publishing, your Gallery and iDisk will be done away within around a year.
The full FAQ can be found in the Via below, and even if you aren't an existing MobileMe user, those iCloud details could end up being highly beneficial.