Here is the way I see things:
At work, I am NOT responsible for the data, someone else is and if the cloud/server goes its not my problem. Someone is PAID (very well I am told) to manage this task its their job to recover data for the organization.
Unless you have unlimited faith in the long term survival of all your cloud based storage systems I would not touch them with a 10 ft pole for personal data.
You need a system:
0) Create a back up plan for your files (movies are not important, your kids photos, important documents, software are mission critical, they are irreplaceable-you can always buy more movies)
1) Buy two identical HDD (1TB-4TB whatever floats your boat) . I have eSATA hotswappable drives both internal and external enclosures, if you prefer USB 2.0/3.0 it will work fine too.
2) If you are on Windows you can download MS SyncToy for free (its actually pretty good for free). The first back up might take a bit of time, but after that its always a synchronized/echo incremental back up.
3) Now that you have backed up to two identical drive, take one and put it off site (like a locked file cabinet at work, or grandma's house)
4) After 1-4 wks take the drive that is at home with the latest back up and put it off site and bring the one that is off site back to home. (order is important, this way the latest back up is walking out with you and there is at least 1-2 copies off site at any given time.)
This way when your house burns down you just walk out with family leaving everything
behind (knowing that you have back up that is only 1-4 wks old that is off site). When you get a new computer you plug in your off site HDD via USB (so you don't need a highspeed internet connection to download 1-4TB of data) and you have EVERYTHING instantly available . Remember your blu ray collection is not going to be top you your mind when you are trying to rebuild from catastrophic loss, its the photos and documents.
If your house and your off site storage burn down simultaneously, back up may not be the biggest thing on your mind, you got bigger problems in life.
IMO, all other methods (cloud based storage) are handy back up solutions to this main method, they compliment but not replace the physical off site storage method.