The additional perks are:
50% bonus miles per flight instead of 25%
$100 standby fee waived for day before and day after on return flights
Complimentary inflight cocktails
One extra free checked bag
The first would be nice. But I hardly ever fly standby; my schedule is pretty fixed. I have absolutely no desire for their miserable inflight alcohol. And I usually take just one bag. So I'm not real motivated, ya know?