One of the things that scares me with the current situation. I also found WebmasterWorld with a Google search. After the site popped up a number of times for webmaster related queries I decided to join and eventually become a paying member.
By not being visible anymore in the major search engines, the number of new users may decrease. For some forums--like the AdSense forum--this might lead to increased quality in the short term, but I am not sure how the community will evolve if WW remains unfindable from the search engines for a longer period of time. A good thread is often not started by a senior who knows it all, but by a newbie who happens to ask the good questions. A community is an organic entity and by cutting one of its sources for new blood, it can change into something unwanted which is difficult to reverse.