At its best "Coffee and Cigarettes" is a fun premise, with a constellation of stars with hip characters in hip locations. At its worse "Coffee and Cigarettes" is the worst improv you're going to see this side of amateur drama school.
Despite good stories by two old working class men and mafiosi, and great performances by a wide range of actors, comedians, rappers and rock stars, you'll be bored to tears with at least three-quarters of the whole movie. Some guidance by the director wouldn't have hurt. At least the most boring stories aren't that long.
This is a hipster film that had the potential of becoming a pop culture phenomenon. See it if just for thinking of all the possibilities that were missed.