I am going to report on my Italy trip in the order that we visited and saw things. There really wasn't any city that was that much better than the others and they all had good and bad policies and habits being practiced.
Florence is a college town so it had the most visible number of bikes parked on the street and number of cyclists riding bikes for commuting and recreation. The city of Florence had implemented separated bike lanes on the major arterial streets that fed the city and bidirectional, colored bike lanes on many of the secondary streets. Most of the secondary streets were paved with cobbles so the smooth bike lanes encouraged use and directed bikes through the heart of the city with little interaction with automobiles.
Florence was the first place that we saw that had bikes sitting around unlocked or just locked to themselves and leaned against shops and buildings. They also used the flimsiest cable locks and chains to secure their bikes. After renting bikes and doing a Tuscany bike tour, I found some inside information about their locking practices. Our guide Bill, from I Bike Italy explained that bikes in the daylight were fairly safe and a small chain was sufficient to detour theft. Night time was a totally different situation. He said that no bike lock was big enough to secure nice bikes so there wasn't any sense in spending the money on a fancy lock just to have it all gone the next morning. He said they just bring their nice bikes indoors and it has been such a part of the routine that they don't think anything of it. He also said that the city has been known to change bike racks without any notice and they would go through and cut all the bikes free, move the rack, and the bikes would either be confiscated by the city or by thieves.
Florence didn't have a sponsored bike sharing program, but had several private bike rental companies. It was very reminiscent of New York's bike rental system and the streets were full of tourists that rented bikes by the hour and see the city from the perspective of 2 wheels.
The bike clubs and athletic groups that bike were very active in the area, since you could ride 5 miles outside of town and be in some pretty fun/steep, rolling hills of the Tuscan countryside. Clubs seemed to be very similar to the ones here in the states and they all appeared to be doing their typical weekend warrior rides or people just out cruising through the field of vineyards and olive groves.
Overall Florence had the best on street bike facilities. Very hip bike culture and commuting. No helmets to be found anywhere, but that is true all over Europe. Very pedestrian friendly with several bike and pedestrian only streets.