Watching THIS video and I like the the hustle and bustle of the city in certain areas. Also, nice little detail when he climbs aboard the small boat and puts the guy in the water accidentally. The zipline also looks pretty cool and allowed them to really push the scale of the buildings/streets without making traversal any more tedious.
Still think not having exploration music is a mistake and I have no idea why they keep leaving it out. The combat animations also generally look lower quality than previous games.
EDIT: Seems like they pushed the "1v1 while everyone else stands around" combat to new heights. Are there no 2 or 3 person attacks like in Batman? Looks really awkward.
When Jacob jumped into the Thames, it looked like there's a slight 'pause' when he was about to hit the water :S