"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
Firewire 2 (1394b) Evidence
1394b (or Firewire 2) was approved this year in March, however, due to the lag time before finalization it was not expected until late summer at the earliest.
For whatever reasons, Firewire 2 did not make its way into the most recent revisions. This, however, does seem to indicate that Firewire 2 will be coming soon.