I'd say Gosling falls under that category right now. A guy who has been earning his stripes for years with some acclaimed performances under his belt but hasn't really found that mainstream breakthrough role yet. He's certainly not an A-lister in my eyes. His movies aren't exactly lighting the box office on fire nor is he a household name. I consider people like Will Smith, Leo, Brad Pitt and present day Robert Downey Jr. A-listers.