Hi everybody! I have done a fair amount of research and even a bit of experimentation to answer your questions here. You can make quick/refrigerator jams using only your Precision Cooker, but long-shelf-life jams and jellies will still require proper jar processing and potentially extra stovetop cooking to get the product over 222ºF briefly according to a candy thermometer.
I just completed the cooking part of a jam experiment - orange & lemon marmalade and kiwi preserves - and am waiting for the mixtures to cool to see what the consistency will be like. And @acs, the plain granulated sugar dissolved completely with the juice from the fruit.
Considering the growing interest, this sounds like a great experiment and blog post to pursue! In the meantime, I am playing with recipes that I find online myself.
If YOU decide to experiment, let us know how it goes! We'd love to hear!