I don't think it was Darksun. I think it was Darksun, Forgotten Realms, Greyhawk, Spelljammer, Birthright, Mystara, Al-Qadim, Planescape, Dragon Lance, Ravenloft...
Ah, the good old days, when you could have 5 or 6 new D&D products every single month.
This is the one thing I always find assuming.
Claims that WOTC has an aggressive publishing schedule.
Have people forgotten the glory days of TSR when you literally had at least 1 new product a WEEK? (it was like comic books...every week I would check my FLGS to see what new comics and D&D stuff was in)