I was told by an Amsterdammer that Amsterdammers don't mind being photographed. It's true, but then, be careful, be tactful, and if someone looks at you like they don't want to be in the picture, just don't do it. I never had encounters with people, but then, I never sought them. I did, however, enjoy my time there, which was in 2008.
I don't know for how long you will be there, but take a day or two to "scout" the areas (I did, and realized that they are very distinct even within a small city). The Jordan and the Spui are the most picturesque (to me), but then the area near the Central station may catch your eye, or the end of the Chinese quarters. The neighborhood around the West Church was my favorite, and if you're going to be there on a Monday, make the effort to go to the Jordan and participate in the street market. Again, ask before photographing vendors. Some don't mind, but if they do, ask if you can take a photo of their wares. Usually, they don't mind.
Leydenplatz is a nifty place for night shots... and for drinks, if the outdoor seating bars are open. 🙂 Walk along the Princess Canal and the Kaiser Canal for pretty picturesque, Amsterdammic shots. I'll try to remember more... and dig out my photos from my 2008 visit.