While Canonical originally pushed heavy their Ubuntu One cloud storage service within the Linux distribution along with their music store on Ubuntu One, they have conceded today they lost the battle against other cloud storage providers -- Dropbox, Google Drive, etc. Other cloud providers offered more free storage than Ubuntu One, their pricing was better for premium plans, and they were more reliable. Ubuntu One support will be stripped out from Ubuntu 14.04 LTS and will also be dropped from existing releases.
The Ubuntu One services will end on 1 June 2014 while users have until 31 July to remove their data before it's wiped. More details can be found via Jane Silber's blog post for the shutting down of Ubuntu One file services.