1) Increasing software mono-culture. A patch on ANYTHING, even an AV update, might bork several different providers completely.
2) The local connection to the cloud.
What if we go cashless, all plastic cards and/or phones and banks, retailer's back offices and payment providers all outsource?
There would be food riots in maybe 24 hrs (c.f. Hurricane Katrina).
Most people will die.
What if infrastructure providers outsource to cloud? If the billing system is inaccessible, you'll not be able to use your mobile even if the Mobile Network is operational.
Electricity, gas, pumping water and sewerage.
This Cloud business has no silver lining.
It's only safe as backup systems to your own systems or for anything you can life without for a week, or collaboration on documents. If your business depends on it, some day you'll lose everything.