I enjoyed the AAAI context activity workshop a lot.
The keynote How to make Face Recognition work (pdf) by Ashis Kapoor showed how to increase face recognition introducing very simple “context” constrains (two people in the same image cannot be the same person etc.). Very interesting work, I wonder how much better you can get introducing some more dynamic context recognition to the face recognition task.
Gail Murphy gave the other keynote Task Context for Knowledge Workers (pdf). She introduces context modelling for tasks in GTD scenarios. Also quite interesting, as completely complimentary to my work (no mobile clients, sensors etc.).
A lot of people were aware of our efforts during the Opportunity Project and the standard datasets we want to put out.
Rim Helaoui presented work about using Probabilistic Description Logics (pdf) for activity recognition, an interesting approach trying to combine data driven and rule-based activity inference. They used the opportunity dataset ;)
Bostjan Kaluza shared the call for more standardized datasets in context recognition in his talk about The Activity Recognition Repository (pdf). A very important endeavor, I already also discussed several times. I think a broad effort in the field is necessary.
All the final papers are up on the workshop website.