Not so fast. If you ask me, reports of the demise of the desk phone are a tad premature. The report can hardly be considered unbiased: OnRelay sells a mobile PBX for fixed/mobile convergence, so calling desk phones obsolete fits into its marketing message -- and the green message is just a bonus.
To be sure, plenty of people are dumping their home land lines to rely on their personal cell phones, and there are lots of theoretical advantages to having all our communications available in one device.
But there are also lots of reasons why our work-provided mobile phones will not soon become our exclusive telecom devices. Ownership and privacy concerns come to mind immediately. No one wants to carry a personal phone and a work phone, but do we really want to have our employers control all our telecom access? Not to mention issues of battery life, device standardization, network reliability and availability, security, and many more.
What do you think? Is there still a need for desk phones in the office? More to the point, is there anyone out there who has ditched the office phone in favor of a mobile device, with or without fixed/mobile convergence?