Cloud computing is transforming data centers.   I highly recommend the Cloud Computing Deep Dive report The 21 page report from InfoWorld discusses how critical resources are sourced and deployed. Security and governance models change. Power and management requirements are altered. If you are transforming your business' data center into the private cloud model, this report is a good starting point.
Mule 3 is out and they have jumped on the cloud computing bandwagon.

The Mule Cloud Connect supports Amazon AWS, Salesforce, and Facebook. Mule 3 supports for JSON data bindings and mapping, JAX-RS, and OAuth in its core functionality. More interestingly, Mule 3 will allow subscriptions to ESB events directly, although most security infrastructures will not allow JQuery to subscribe directly to ESB events.

A big focus on Mule 3 has been ease of use, meaning less cost for businesses in terms of development time, deployment, and maintenance.