Working 52+ hours a week, having children, being the Mr. Fix it guy around the house...who has time to create their own worlds anymore? Adventure paths, Chronicles and many of the modules have given me the ability to continue to run good games with alot of background data with a very small amount of prep time. Add in the OGL to make changes or add something of my own design and its a win win I think. Especially if you want to convert everything to D&D4.0, Rolemaster or Savage Worlds. I have already found alot of wiki information on the area in which I am running my campaign.