Centralisation/decentralisation Insourcing/outsourcing
This is another one to add to the list of cyclical fads.
Yes Cloud will get bigger, but then I reckon that there will be a reversion to on-premises. A few more security scandals, a few more changes of ownership of players in the market and people will be running for the exits.
The "edge" that corporates strive for is how to differentiate oneselves from the competition. "Everything we do is in-house, we care about security" is a strap-line that will be wheeled out as a differentiator when the cloud cycle takes a downward turn.