Today, a fresh set of trends and technologies is changing the way that we build computing systems and operate them. Two of the biggest are virtualization and cloud computing. Virtualization effectively decouples operating systems and their applications from server hardware, and thereby makes it easier to physically move them from one machine to another. Cloud computing is changing where applications run - from on-premise to out-in-the-network.

Business dynamics are also changing. Even if it's often just a self-interested concern about their power bill, we are starting to see a greater awareness of environmental issues among those responsible for operating datacenters. The current economic climate is also forcing more systematic thinking about costs in general, including those associated with overall complexity and the security and resiliency of large distributed infrastructures.

These trends intersect in powerful ways; a new wave of computing is gathering momentum as a result. And open source is once again playing a major role.