I like to divide the cloudosphere into four groups: monotheists, polytheists, atheists and agnostics. Monotheists believe in one and only one cloud, tying themselves closely to a single vendor (e.g. Netflix on Amazon). Polytheists are focused on supporting all clouds, promoting the value of each in advancement of their business goals (e.g. RightScale). Atheists do not believe in any cloud, and are a shrinking group that will likely soon be added to the U.S. endangered species list (e.g. Larry Ellison before 2011). Agnostics believe in the cloud, but have a healthy mistrust that drives them to steer clear of single vendor lock-in.
I will confess to having once been a monotheist before flirting with polytheism and finally settling on agnosticism. But in my weak moments, I sometimes wish I could return to being a monotheist. ;)