I did some early IT surveys of UC plans and I think there needs to be a change in the questions because of the rapid uptake of mobile smartphones by both consumers and business users (as opposed to desktop PCs). This shift will place more emphasis on hosted services that are personalized (and therefore controlled) by individual end users as opposed to premise-based services. That also means the real value of UC to the enterprise will depend on the number of individual end users and their job responsibilities that benefit from UC capabilities (not just cost savings).
Another aspect that seems to be overlooked by your surveys is that UC is not just about "person-to-person" contacts (voice calls, conferencing, IM, email, unified messaging), but is now open to the benefits from increased automation of process-to-person information delivery and time-sensitive "notifications." That falls under the label of CEBP for business process applications that is really based on messaging flexibility, as well as online interactions. It applies to end users both inside and outside of the business organization, especially for proactive customer contacts, where revenue-sensitive services reside. So, in planning for UC, that is a big target for business planning that IT can't define by itself; they need LOB management to define and prioritize business operational problems and get creative about solutions. The more you can enable direct access to information without involving people in the middle, the more business operations will be better.
As you mentioned in your article, the real difference between a large and small enterprise for UC functional requirements is disappearing - it is only a matter of quantifying the application services, not using different technologies. With the increased complexity of UC, the fact that it is becoming primarily software in "cloud" environment (and therefore dynamically changeable, day-to-day), makes ownership and maintenance of UC technologies, especially the mobile endpoint devices, by in house IT management, extremely difficult and questionable. UC and mobility do not lend themselves to CPE and enterprise staff development!
SOA and cloud computing services are more amenable to the vision of UC that supports both individual end user job needs, as well as personalized, consumer services, that will be location, network, and device-independent. Businesses, both large and small, will have to exploit hosted or managed services to provide and support UC infrastructures and vertical applications, as well as mobile and remote end user needs for information access and person-to-person contacts. The big challenge is the migration to such a technology future and how to do business with the various providers of this converged, but more complex, technology environment, which will be different for every organization and their various users.
Personally, I like this idea. I'd be very happy using a good VoIP-enabled mobile device for ALL my communications needs, and pretty much avoiding my office desk phone. (I'd be happy ditching my home phone too, but only to go to VoIP. I get crappy cell service in my house.) But I also agree that the UC vendors I've talked to are not yet at this stage...
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