Maybe it's the heat, or just a coincidence, but it seems New Yorkers are starting to get agitated. And they're making sure those around them are aware of their rudeness/stupidity/lack of respect. Two recent news clippings underline this:
In both these stories, it seems a lack of respect pushed these guys over the edge (one a little more dramatic than violent).
It could just be timing, but these are two examples of folks saying "enough is enough" and taking the steps they feel are necessary to right what they think is a wrong.