That looks like a really interesting conference, so I am sorry I missed the live streaming. Did you get a chance to go see some presentations? I would be especially interesting in the one on Documents as Monuments. Many monuments have been lost to wars or just neglect and city planning, and old engravings are a way to preserve the memory. I thought it was interesting that that specific talk was given by someone from the Netherlands, and I was wondering what the background of the talk was.
Our Wiki Loves Monuments photo contest will improve the coverage of monuments on Wikipedia as these monuments stand today, but we need another contest in order to improve the coverage of historical monuments in old engravings, paintings, sculptural and tile tableaus... I am thinking of churches of course, but there are many others as well. Yesterday I was at the Dom Cathedral of Cologne (conveniently located across from the train station) and was astonished to find out that more than 50% of it dates from the 1880's.
It was nice meeting you in Berlin - we will always share the special memory of the bongo-drum players appearing in our dorm room at the hostel in the middle of the night!