Openstack is free, and therefore is likely to become the dominant Cloud Management suite for most of the world, until prices of competing products come down. This opinion is based on the concept of Cloud as a Utility where Utility pricing may dominate the user's selection of Cloud services provider.
Already today, limited Cloud services are free to users.
The usablity of the management interface means that even non-IT literate people can use it with training.
The Linux administration skills required to install, tune and configure it are high, although the use of scripts produced by third parties gives a non-custom setup very quickly. As time passes the numerous scripts and hopefully GUI installation and configuration will become standard.
Since writing this review companies like Cisco and VMWare have joined the OpenStack Project. It would appear that these companies would be in competion with Openstack.
Established I.T. companies are seeking move their business models towards "The Cloud Model"-some will fail.
I define The Public Cloud as primarily a cheap mass market easy-access online computing resources whose running costs are mainly energy costs.
Private Clouds have a role but will probably use most of the cheap unbranded multi-cpu low-energy Cloud Servers and OpenSource software like OpenStack.
The old I.T. Giants will struggle to maintain their markets in this model. These include Dell, HP, IBM, MS and even Cisco.