Yes, they are.
However, a 901 atomizer will not work on a "sealed" 808 automatic without modifying the center post on the atomizer connection, or modifying an 808-901 adapter. Modifying an adapter is easy, but you have to reset the center post every time you remove the atomizer and it becomes a hassle. The other option is to take a dremel to the center post of the atomizer and cut grooves along the threads to allow airflow. The reason for having to do this work is due to the fact that a "sealed" 808 has moved the airflow from the center of the connector to the sides. A 901 atomizer is not designed to allow for this modification and as of now no one has come out with a proper adapter to allow 901 atomizers to work on the "sealed" 808's. A 901 atomizer will work fine on a manual 808 since airflow isn't required to activate the switch.
I don't own a dremel, and even if I did I wouldn't wish to waste money trying to modify atomizers myself.