As I've written earlier, at this year's RecSys we're organizing a challenge on context-aware movie recommendation. The challenge is part of a joint event together with the workshop on Context-Aware Recommender Systems (CARS) and I'm anticipating both events to be very interesting.
We're done with the reviewing and currently waiting for the camera ready versions to come in, as well as onepagers describing each paper's algorithm (these will be evaluated by an expert panel consisting of very distinguished researchers).
Organizing this challenge so far has been an extremely valuable experience. From the first abstract idea to creating dataset to answering all the different questions and inquiries from the participants. Even if it has taken up a quite large portion of my time for the last couple of months, it definitely has been worth it and I would recommend any PhD student to try to get involved in organizing at least one of these as there quite a lot of insight to gain.
We'll have 10 papers presentations at the workshop, 5 long and 5 short, and I must say I'm very happy with the quality of the accepted papers and really looking forward to the presentations and discussions at the day of the workshop.