Originally Posted by swh
I used to get traffic on other IFR aircraft well before ADSB, and even before alphabet airspace, nothing has changed.
Yes it has. The quality of traffic information available to ATC has improved significantly:
IFR traffic is ABC, a PC12, departed Smithville time 25, climbing FL150, estimates ANGUS at time 47
vs
IFR traffic is ABC, a PC12 just departed Smithville, ten miles in your eleven o'clock, opposite direction, passing six thousand eight hundred
Which gives you a better idea of where to look to find the other aeroplane?
Like someone said earlier in the thread, ADS-B is the greatest thing since sliced bread. It'll be even better once everyone has it.