Yes, Better Call Saul will have cameos from other Breaking Bad characters

Gilligan says as much in this new Hollywood Reporter profile, in which he discusses how, despite Saul’s lighter comedic tone, he still intends to maintain many of Breaking Bad’s visual elements, which he’ll accomplish by directing the debut episode and sitting in the writers’ room full-time for at least the first season, bringing back as much of the crew as possible—and, yes, also getting Bryan Cranston and Aaron Paul in there somewhere. “Personally, I'd have a hard time resisting putting all these guys in for a cameo or two every now and then,” Gilligan says of his former cast, as the article notes that both Cranston and Paul have “expressed interest” in popping up. “Oh, excuse me. I should have knocked,” perhaps Cranston will say, accidentally stumbling into Saul’s office, then winking at the camera.