This is a great question. I always make it a point to learn all the names in the first class meeting. By the end of the class, as I present a previewof what the next session will be about, I say something like "It has been my pleasure to welcome all of you to my class" and then I say everybody's name. I always bring a seating chart to the first class, one that would allow me to assign names to each spot. As I ask each student to introduce themselves, I write their names on their place in the seating chart. During the class, I check the seating chart as I address the students. During the brake, I make sure to go over the names again and again in my memory. Usually, at the end of the class, I'm ready to remember them all. Granted, my classes are ususally not that big, 25 students max.
As to the pronunciation, I ask each student how they want their names to be pronounced, even if it's a fairly common name. It is their name, it is a marker of their identity, and as such it should be respected by all, especially the instructor. (The example of Colombian soccer player James comes to mind).
