I was fortunate to visit New York City after a trip to DC for a FHWA Workshop. I met up with one of the bicycle planning staff that has implemented the 1st Avenue bicycle facility. The bicycle lanes were striped on the left hand side of the street to eliminate conflicts with buses. I was not initially enamored with the conflict of left turning traffic, but I found it more natural for a left turning vehicle to yield to the through bicycle traffic then the right turning traffic might otherwise. I could see a possible research problem statement forming for the National Cooperative Highway Research Program of the Transportation Research Board. One element that needs further study is the effectiveness of the green bike box with the person on a bicylce expected to make it across two or three lanes of through traffic. The conservative engineer makes me wonder if someone would weave over to the right hand side and have a conflict with traffic that has a green. Education of cyclists would be key to make this effective.
Signage is pretty good along the corridor since this is a rather new implementation. In this case, there was an exception for bikes at one of the mid block intersections that they closed down to reduce conflicts. In this case, they eliminated the access to vehicles, but left the path for cyclists and pedestrians to the local street. It encourages a little more mobility, actually reducing a conflict for motor vehicles (previously there was an occasional left turning vehicle).
The other treatment on this facility that was particularly innovative was the way they created green space within the median. In this case, they stripe the bicycle to yield to pedestrian and bicycle traffic within this median in order to allow an uncontrolled intersection. This is something we can use for the Portland to Milwaukie Light Rail line intersections as opposed to signals that might otherwise result in needless delays.