Apple Users

It's not clear how close to that they will get to that in iCloud this year, but this is somewhat encouraging:



While Apple shows no sign of throwing out the file system whole-hog just yet (and good thing, too), there will be a new option popping up with Mountain Lion: iCloud document storage, a central online repository for your files, images, PDFs, and such. You can create new documents within iCloud directly, add documents from your Mac by dragging them into the window, or send them back to your Mac by dragging them out.

http://www.macworld.com/article/1165496/ten_exciting_system_changes_in_mountain_lion.html

I see a share button at the bottom of the window. I know you will be able to select Twitter, Flickr, Email, etc... but will there be a link to the cloud you can share, like you could with MM? Dunno.

You might want to consider Dropbox as a back up. It's not 'Mac,' but it's just a 'feature' as Steve Jobs said.

Which brings me to another encouraging detail about the future of iCloud and file hosting. After Dropbox refused a nine-digit offer for the company from Apple...

'Jobs smiled warmly as he told them he was going after their market.'

http://techcrunch.com/2011/10/18/dropbox-said-no-to-nine-digits-acquisition-offer-from-apple-steve-jobs/