yeah but who has an android pc/tv/smartphone/laptop all linked to a server or home network? your entire life can be tethered with you wherever you go. Who is to stop someone from mugging you, taking your cellphone, and accessing your files from your home computer if it's tethered to the network or if all those files are already floating around inside your web browser and the cloud? Who's to stop a guy from having ubuntu like you in an apartment complex with access to your network from tethering himself to your cellphone and leaching off your talk and data plans for his own rooted phone? The list of potentials is larger and yes mostly depend on user stupidity but it is entirely possible if ubuntu becomes popular enough for it to become the OS to hack to mess up peoples lives for their gain. having this open source is only fuel for the fire.
I know this is very "the sky is falling" mentality and it's chances of happening or not as big as I am painting it but then again I was stating the possibillity of this turning ubuntu from open source linux to something closed and independent in order to make it a profitable business and protect user data. If ubuntu becomes popular enough for my mentality to be a potential reality you know this man is gonna make ubuntu into a low cost alternative to windows/osx venture for "our protection."
Still think it's a cool idea though. Heck blackberry has been dabbling in this and hinting at it's potential uses with playbook and phone compatibility. Ubuntu has a good idea; just needs more ironing and future proofing.