I personally, have bought modules. But my business has not. They look at Sharepoint and say, "Hey it's free" and it looks the same and they see the price.
I had to debate hard to use DNN instead of sharepoint, but the reason they went that direction was because of free modules, open source and good community.
It seems to me if the Active Directory authentication piece was documented just a little bit, it would be easy for people like myself, to simply go in and make the changes.
What bothers me is that it is in the core and there isn't even easy finable instructions on how to use it. I know Tam is out, but it still seems like it has been rushed to market a bit.
With that said, I am a huge DNN fan, and I have used Tams Gallery and Forums from long ago. I just wish it was better documented and I think that I am allow to have that wish.
Stuart