I read the Rennlist 911 forum just about cover to cover when I first got my 911.
As others have said, there are a couple of really smart folks there who post a lot. There are also a few hundred arrogant asses--easily spotted my the "Rennlist Member" under their name.
Read any controversial topic and you'll see plenty of their posts, which are generally egocentric and dismissive in tone.
Good reading for background, but when I need help or want to discuss an issue with knowledgeable and friendly Porsche enthusiasts, I come here.