Virtualization and SOA
"The word architecture is generally quite misleading for describing what most companies have today," write John Hagel and John Seely Brown in their new book The Only Sustainable Edge. "Architecture calls forth images of the neat schematics of an architect who is carefully thinking through in advance all the needs of the occupants of a building and designing a structure that optimally meets these needs." 
As the authors explain, "Today's IT architectures are far better described with a geological metaphor -- imagine geological sediments accumulating, one on top of the other, in different continents. The sediments are the various generations of IT that have been deployed in large enterprises -- mainframes, minicomputers, desktop computers, servers and mobile access devices in terms of computing power and equivalent generations of electronic networks. Rather than ripping out previous generations of technology and designing greenfield architecture to more effectively exploit the capabilities of new technology, companies deployed new technology next to existing platforms. Where necessary, they implemented custom-designed connections to create a semblance of integration. These custom connections were also necessary to bridge departmental silos and enterprise firewalls..."
Unfortunately, these hardwired connections and ponderous approaches have failed to make IT capable of adapting to the dynamic changes occurring within hyper-competitive, global markets. To address this challenge, Hagel and Seely Brown offer an elegant way of looking at the solution. They argue that virtualization architectures will enable us to orchestrate and leverage distributed hardware resources, while service-oriented architectures -- based on the loosely coupled connections we know and love -- will enable us to marshal software resources.
While virtualization promises to simplify the hardware management task and make computing resources "highly adaptable," SOA promises to help break down the "prison walls" erected by conventional software application platforms -- making software resources more flexibly available.
"Both of these emerging technology architectures depend on, and in turn help reinforce, the trend toward increasing commoditization of hardware and software components," they conclude. "Commoditization of the underlying technology components allows companies to reconfigure the arrangement of these components, as business needs change. Paradoxically, this commoditization facilitates new and more flexible technology architectures that increase, rather than diminish, the potential for strategic differentiation of the businesses deploying these commodity components."