Who cares if it's a feature, not a product? The question is - is it a vertical or horizontal feature? You can't sell cut-and-paste, because there's no advantage in having the same cut and paste on every device (no horizontal advantage), and you'll lose out to the manufactures ability to bake deeply integrated cut-and-paste into the OS (big advantage for the vertical implementations). For file sync, there's not a huge need for vertical integration (OK, Erik Sink's written about how different platforms can be a PITA - http://www.ericsink.com/entries/quirky.html, but it's still possible if you have the resources and smarts); and you have a huge advantage over horizontal players, because people want their data safe on different devices.

There's a little company called Microsoft, which sold OSes. The OS is just a feature of computers. They had the chops to smooth over the vertical issues (drivers, etc), and got boosted by the horizontal advantages (your programs work on any computer with Windows). So the OS became a product, not a feature, because it carved out a large horizontal niche, blowing away the vertically integrated "features".