I signed in yesterday to upload some photos and was encountered by this:
 

 
I suppose 50GB storage and 2GB file transfer for nothing was too good to last.
 
 

 
Mind you, the upgrade from the free account offer - $25/£16 for three years @100GB storage - seems pretty reasonable.

A good reason never to use the cloud as the only place your stuff is stored. Businesses have a short lifespan, and internet businesses some of the shortest. If this business cannot keep up its free service, there is no guarantee that it will be there in three years. The issue is even more relevant when you are buying stuff that you never get to own. Your music collection is not old vinyl anymore, it is the promise that the guys who are storing it for you, or authorizing it to play on your new smartphone, will still be there when you want to listen to it. 

Although I do agree with Slart, I have begun using the Amazon Cloud Drive as my offsite storage.  $59.99 per year for unlimited storage plus I have more faith in Amazon than most other companies.  I figure that by the time they do away with the cheap price I should be able to afford another hard drive (or may do my own "cloud" storage).