Even for a photowalk, customizing the uploadwizard will be good. Generally people upload elsewhere, never upload since people dont return to a room and sit / upload (unless there is a conscious meetup happening).  There was a Chennai photowalk which failed on this part, and people met, clicked pics, but many never came online(30 pics came from 15 people for a whole day of hunt). HPN did some photowalks in Bangalore / Mysore, he had a better upload rate, though am not sure if everyone had uploaded every pic they clicked.