I think that syncing the pim's around my Ubuntu landscape is a missing feature. All kinds of Calendar software like Evolution, Kontact or Thunderbird (with lightning) are able to sync. It is only a small step to finish this issue, I think.
It is possible to stream music with Ubuntu One, but no sync with local Calendars or Mobiles. I think that the pim syncing feature is more important an useful as the music streaming one.
I only get an account on Ubuntu one for pim syncing and mobile sync option. Right now Ubuntu one closed this feature. For what really I should keep this? For music streaming?
I can use Ubuntu one as a backup system for my Ubuntu files?