Looking at the direction that the technology/hardware is going is a strong indication that convergence is not only coming but is already upon us though in it's earliest stages. Most consumer devices (digital cameras, video cameras, cell phones etc.) already have still and motion capability to some degree, with some of them doing a very good job of both. There are several companies developing and already marketing professional grade devices that give high quality still and motion photography with a few devices doing so simultaneously. If this isn't a harbinger of things to come, I don't know what is. Or is it?
The interesting thing to me about the arguments about convergence is that they focus on the technology/hardware that already has been created, or is in development, or even speculation on future technology that again has yet to be defined that will be used to create and distribute these still/motion hybrid images. The real question that people seem to be avoiding is the difference between how still and motion photography is produced. In every professional still and motion photography shoot, with few exception, there involves some sort of artificial lighting or the manipulation of natural light. The difference between the two is that most still photo shoots involve strobes (flash) and in all motion photo shoots they use hot lights (lights that are constantly on). Because of this difference, motion shoots have higher budgets, bigger crews and take more time than the vast majority of still shoots. To create high quality still and motion photography simultaneously, every shoot would have to be done to the scale of your typical motion photography shoot. I doubt many still photographers are going to start hauling around the equipment and crew that would be necessary for this. This is not to say that I don't think photographers will start producing still and motion images but you can't do both at the same time and achieve the same high quality for both, at least not without the budget of a motion picture/commercial/tv project.