The implication seems to be that you don't get audio through 3 segment 3.5mm plugs, but you do through 4 segment ones. In my experience, 3 segment plugs worked fine before the update and continue to work after it. It does seem to take a fraction longer for them to be detected (and the headset icon to appear in the notification bar) now.
Unfortunately not the case. Yes it's true that the 4 segment one works (without much delay) the 3 doesn't do anything. Used to work fine before the update without any issue.