I recently switched my offsite backup solution (for personal files) to Google Drive. Here's why:

• I back up a lot of home movies and Google Drive has a great feature that automatically transcodes AVCHD movies and makes them available to view online. So now sharing movies with the rest of the family is as easy as sending them a link.
• The storage solution is backed by a large company that's not going anywhere soon - important consideration when backing up precious data.
• It's relatively cheap. Works out to be about half the price of dropbox. Also, as a side-note, I expect Google storage will always be able to undercut the competition due to the scale at which they purchase and maintain storage for their existing services. Competitors such as Dropbox either run on third-party storage solutions (Amazon's S3 for example), or provide their own but would not be able to match the economies-of-scale that Google can.
• It scales up to terabytes - so as I add more and more data over the years it will always be able to match my storage needs (although it might hurt my wallet somewhat).

The biggest problem with Google Drive for me is that they do not provide a Linux version. Some third party software called Insync is available which allows me to sync to drive, but it's still a beta version (which is a little worrying when backing up important data). Also it does not allow me to only sync some folders from my drive to my linux machine, which is a little annoying as this is a nice feature of the Google drive Windows client.

Ah well, can't have everything I suppose (Google please release a Linux client!!!)