One myth missing
One myth is missing. It should be "Nobody needs cloud" or "Cloud is more than marketing hype". Or both, let the user decide.
It is true that Cloud allows to pay only when you need. The downside is that if something interesting happens, everybody will need computing power at the same time and somebody or, if the Cloud is 100% fair, everybody will not get it.
One (1) such event will turn years of "optimization" into a net loss.