Last year, as Demomobile 2003 was nearing, I developed a mantra of sorts. As often as I could, I asserted that mobile technology had turned us into "always-on people" - empowered buyers of technology who would usher in a new era of "device computing," in which computing would shift from desktop and laptop PCs to smart phones and handheld devices that can access data anytime, anywhere. Now, a year later, I think I was right, even if I did have it backward.The computing shift isn't about hardware devices, as I initially thought. It's about the software architectures that support those tools. Rather than device computing, we're moving to an age of service-delivered computing. In this model, service providers - whether application service providers (ASP), corporate IT organizations or even a desktop computer you manage yourself - make applications and data available to individuals who connect to these services through a variety of secure devices.Certainly, we can understand and accept this trend in the form of managed software services - ASPs such as Salesforce.com or NetLedger. Enterprise IT has opened centralized applications to data input from and reporting to mobile workers, and now enterprise applications are being architected with mobility integrated in the business process.You can see the next ripple in this spreading paradigm in data services offered to mobile phone users. As higher broadband wireless networks come online, carriers will offer a range of data services that go well beyond news, traffic and weather. Carriers have a huge and virtually untapped opportunity to become the data center for their mobile wireless customers.The ripples will extend even further, as presaged by AllenPort, a Philadelphia start-up that in February at Demo 2004 introduced a service-based computing architecture, in which applications, configuration information, data and even Web history and bookmarks are stored on a central service. The company is finding traction with broadband network operators that see the low-cost hardware, high-value service model as the right approach to delivering computing functionality to their customers.AllenPort might be the most public example of this new service-delivered computing model, but the company is by no means alone. At Demomobile 2004 on Sept. 8-10 in La Jolla, Calif., we'll highlight at least two companies making big bets in this area. (To register for Demomobile 2004, go\u00a0here).Will service-delivered computing be widespread in a year? Two years? Three or more? While the timeline might be a mystery, change is afoot, marked not by devices but by the services to which those devices connect. Change is driven harder and faster than ever before by those empowered, demanding, always-on people.