"Documents you’ve written, presentations you’ve prepared, spreadsheets you’ve made — your iWork apps can store them in iCloud. Which means you can view and edit the same document, in its latest state, on all your devices. And since iCloud automatically updates any changes you make, you don’t even have to remember to save your work."

But I already do this on Google Docs, and I don't have to buy a Mac to do it. In fact, I don't have to buy anything to do it; I already have a desktop/laptop/phone, and Google Docs is free of charge. Plus, most people I know already have Google Accounts, so sharing is already implemented.