There was an incredible amount of productive hacking and discussion at the hackfest, covering the lower parts of the stack like Cairo and Pango as well as the GTK+ core and related work like toolkit web integration.
Until I get round to writing things up, I refer you to Emmannuele‘s posts. He summarises some of the graphics topics that came up and I would echo his sentiments about what a well organised, fun and dynamic event this was.