I'm not sure if I'd agree with that.
(1) Cloud has some major privacy issues, as well as data integrity issues, since you're relying on a 3rd party provider to maintain backups.

(2) Symmetrical gigabit Internet plus IPv6 would allow an internal server to be accessible from outside a company at the same speed as inside the office. One of the major advantages of the "cloud" today is that it's faster for mobile/roaming users -- with a sufficiently fast link, this disappears.

(3) Any sort of worthwhile cloud storage costs money, per month or per unit of data.

Assuming that we get to the point of having gigabit fiber be common, the future might well be composed of modular NAS systems. Think SpaceMonkey, except with the ability to replicate between four or five different devices vs distributing the backup between random SpaceMonkey devices.