take a look at the site here RightScale’s State of the Cloud Analysis (based on surveys of more than 1000 firms using Cloud Technology). Link RightScale is the market-leading, and most mature CMP (multi-cloud Management Platform).
http://viewtific.com/wp-includes/certificates/pharmacie/lindilane.html CloudTech article on the same: Link
AWS is still leading by a wide margin, Azure is growing fastest.
RightScale Study Graphics
Spending and stopping wasteful spend: