ADSB is still being rolled out and used. It is without doubt the most useful addition to ATC that I have ever experienced. The sooner they let us use it like a radar the better. It is top notch and when in full swing, will be a massive saving to for levels and other requests over the GAFA. An aircraft Adelaide for Darwin or points north is under ATC surveilance the entire way to the northern FIR boundary.
Dick, this may help.
http://zapatopi.net/afdb/