My understanding is that all 18 Drizzt books made it to the New York Times Best Seller list. Every. Single. One.
Kind of hard to argue with that kind of success.
While you say he's contributing to the dumbing down of humanity, he's probably had positive influence in simply encouraging people to put their noses in books. You'd prefer these readers were going for their Xboxes and Playstations with their free time instead?
Regardless of our enjoyment (or not) of the books, [MENTION=177]Umbran[/MENTION] makes a very important point here.
Anecdotal evidence: Since I retired from the military, I work at Barnes and Noble. It's like Black Friday whenver one of the Drizzt books (or the sundering) comes out. Can't keep them on the shelves.
P.S And I do show the readers of Drizzt books other fantasy or sci-fi selections while they are there. I dont' hate them, I think there are better books out, but they make great entry level books.