Apple could sign up as many as 150 million iPhone users to its new iCloud service, according to projections based on a survey from RBC Capital Markets.

iMessage also should be a hot item, according to RBC, also with 150 million iPhone users.

Looking down the road, RBC believes Apple will add additional services through iCloud, including audio and video streaming, photo and video sharing, hosted Time Machine backups, and document management and storage.