[luke_s]

I have just completed an R&D project for my company on using JQuery Mobile, with knockout.js, so perhaps I am qualified to answer this.

As another commenter pointed out JQuery Mobile (JQM) is following on from JQuery UI, not from straight JQuery. Knockout.js is a databinding and templating system. As such JQM and knockout.js are complementary instead of competing. Our system used knockout for databinding into the JQM UI.

My recommendation coming out of the R&D project was to use knockout for production apps and to continue to watch JQM, but not use it for production just yet. JQM is still evolving rapidly - there were a number of major changes made during our R&D project. We also ran across a number of issues making JQM work with knockout. For example JQM didn't like knockout changing some of the HTML dynamically, after JQM had been initialised. The JQM team are aware of the problems dealing with changing HTML via javascript and we saw a number of fixes committed during the course of our R&D project. One day soon JQM will be very good, but its not quite there yet.

Furthermore not every mobile application will benefit from JQM. Unless you are building an essentially forms and data driven application, it may not be very useful. Depending on your needs you will be able to get very far by using knockout to produce clean semantic markup, then just applying CSS over the top.