As of 08/2016, only Terminal 3 (Emirates flights) arrivals and departures has the passport scan enabled smart gates installed (similar to the UK smart gates).

The departure part is tricky as the gates installed on the right side (only one gate), as you go towards immigration, are enabled with passport scan departure.

I've activated my skywards blue card last week but I have not had a chance to use it. As of now, terminal 1 (all other airlines) and terminal 2 (fly Dubai) have only egate (smart card) facilities for arrival and departure.

It's highly advisable to have both passport and skywards card registration because it literally takes 10 seconds to go through immigration.