Here's an example of why computer users should NEVER trust "the cloud".
The "owner" of the cloud can change or dismantle it at any time. Or they could just close down. If that's the case, and you trusted them with your data, where would you be?
Yes, I know that Apple has created "iCloud" to replace MobileMe. But there are other times in their history that they've just "left users hanging".
It's kind of like "owning gold" -- if you don't have the gold in your possession, you don't really own it.
Same goes for data -- if you don't have your data under YOUR control, you don't have control over it.
I've been a Mac user for longer than most of the users of this forum have been alive. I would NEVER "trust" my data to anyone other than myself. Doesn't bother me to see MobileMe go, as I never tried to use it (or any Apple "online service" before it). Same for iCloud -- I won't be signing on.
When it comes to protecting your data, forget the "cloud", and keep things down-to-earth, just as you are.