Interesting, I was in Hamburg in Dec for the CCC conference (Which was great btw) and stayed for new years eve. I was curious why so many police were around downtown but figured it was just due to the massive amounts of fireworks everyone was setting off. Do you have any good sources to get more information on this?
The underlying situation is pretty complicated and dates back to developments in the 80s (Hafenstrasse Hamburg etc.), I doubt there's good english references.