Dev tools could potentially make this game huge. D:OS had dev tools that didn't really catch on but this being D&D might make a big difference. I hope lots of good modules come out in the likes of what was produced on the NWN toolset.
I have great memories of playing in a persistent world from NWN back in the day.
I'm really more interested in what was said about converting existing modules/campaigns into the engine. i.e. Campaign Raven Loft or Modules like Shadow Dale etc.