This latest is a collection of open source vendors from around the world -- France, Japan and Brazil (along with Mandriva Nexedi, and TioLive of the U.S.) organized as the Free Cloud Alliance with the idea of selling an open source cloud stack.
Fact is it's not vendors who need to ally in order to assure open source and interoperable clouds. It's customers. Rather than following the siren songs of any vendors, customers need to get together, share war stories, and come up with their own list of demands, then enforce them with their money.
It's the disorganization of cloud customers that is the biggest danger to open standards in the cloud. Most are scaled enterprises, and thus don't think they need to talk with folks who might be competitors. But they do.
Customers know that, at the end of the day, openness is what they want. They know this because they want to be open to leave their cloud vendor and take their stuff to another one without tearing everything apart.
Vendors can't really represent this idea. They are on the wrong side of the table for that.
Many, many years ago user groups and user societies were a powerful force in computing. Folks got together to see the latest stuff, and freely debated its merits among themselves.
That's what clouds need most right now. An enterprise-led user group. You can start it online, then meet over drinks, then start scaling it up. Do it informally, without a press release, until you have a program you want others to see.