This website is a great community of students, artists, and developers that simply share knowledge and resources. It has many parts to the site that I have yet to explore in-depth, but the main areas that I've interacted with are the news, forums, and wiki, all of which stay very active daily. The news section showcases mostly the latest developments of projects by artists and developers posting content in the site's forums, and so the forums tend to be the most active areas on the site, or at least through my experience. In any case, the forums span a wide range of topics, some of which include scripting, Unity, 3D art, etc., but more importantly are the dynamic interactions with other community members.
And this is what I really find most valuable about the site: the feedback. For the most part, the feedback is honest and valuable, particularly that which comes from professionals interacting within the forums. This feedback process is such a key part of the design and development process that I've learned to truly appreciate it to get better.
The wiki's on this site are also a great resource for various tools and methodologies since they collect many tips, tricks, and guides provided by users. It's open-ended with guidance sourced from many people, but I think the vetting is done in such a way that the most relevant and valuable guides are preserved. These go beyond simply tools and how to do specific tasks in any one software. For instance, it includes guides for character art, environment concepts, etc.