I think that may be Newspaperguy's point: culture, not paint, is the determining factor in bicyclists' safety. You can paint lines on the road, or even create new pavement, but if motorists don't think you belong in traffic, you're not any safer.

The city of Seattle has been implementing a bicycle plan, much maligned by non-cyclists, that includes many miles of bike lanes. This has sometimes resulted in replacing a traditional four-lane arterial with a single car lane in each direction to make room for bike lanes. The bike lanes are usually right next to an endless row of parked cars along the curb. Personally, I felt a lot safer when I could just take the regular right lane. Now, on streets that used to feel totally safe without bicycle infrastructure, I'm actually pretty nervous at times, just waiting for an inattentive driver to pull out or open a car door in front of me. I would have been much happier if the city had taken that bicycle infrastructure money and used it to improve the condition of our surface streets, which is actually unbelievably appalling.