If WT is completely packed, then the respite of the five or so rows of segregated WTP may well be worth it alone.
Seat pitch is 38" compared to 31" in WT, the seats have slightly more recline and are slightly wider with a footrest, you get a newspaper, wine in a real glass and get served before the WT lot (although the food is the same). Seating configuration is 2-4-2, as opposed to 3-4-3 on the 747 and 3-3-3 on the 777.