Yes, in my opinion. Neither is a theist. Where they differ is in the emphasis they place on the burden of proof. The atheist might critize the agnostic thusly: "Why do you even consider the possibility of X when there's no reason to do so? If you are open to the existence of X (with utterly no evidence for X) then why not UFOs, ghosts, etc.?" So the atheist would view the agnostic as incapable of deciding when there's nothing to decide. I don't know if I'm explaining this well at all.