a cloud, really, or my idea of a cloud. If it is really just a synchronization conduit, whereby I have to have local copies of any pictures/music that I have "uploaded", it loses appeal. The whole point of centralized storage is so that I can have a theoretical infinite amount of pictures and music in the cloud and merely use my web-enabled device to display it.
This is the method behind Google music (which has substantial problems) and Picasa. All my music and photos are on their sever. I can listen/view via the internet, or I can selectively download items to my phone, as I did for my flight to/from the west coast, for times without internet access.
This was what I assumed iCloud was going to be when it was announced. Color me disappointed. Maybe it is more useful to those with iPhones who sync contacts and such. To me it is just replacing a USB cable with a cloud, and my iPad storage limit is still the limit.