Given the US government's cavalier atitude to private files stored on Megaupload (yes, it was also used for perfectly legitamate business as well as piracy) and its renewel of claiming jurisdiction over all data held on US servers even by non US entities, the cloud is highly unlikely to take off the way people keep predicting. Store something that's legal in your jurisdiction but illegal in the US? You could well be facing court.

Secondly, the realisation that once it's on a cloud server it is out of your control. The Instatgram fiasco demonstrates this kind of attitude nicely.

Private cloud, hosted on servers in your company's legall jurisdiction with a detailed contract specifying what the host can (and cannot do) with the data may be acceptable (or even larger companies hosting their own?)

Until the legal aspects are sorted out (never mind all the security aspects, crap internet access in many places - I loved the bit about uploading via a 10Mb/s. Here in the UK a download of that speed can often be considered good!), cloud is not something I would recommend to anyone.