I learn a lot.
You get people from all kinds of backgrounds posting here, with varying expertise in and opinions on all sorts of subjects, including technology. It's also a great place to discuss issues - whether it's light stuff (like the bazillion Peyton Manning threads) or more serious issues (Uganda and the LRA).
Plus, I read most of the articles on the main site and I like to see users review and weigh in on new CPU architectures, the latest graphics cards, case designs, etc.
I also learn a lot just by researching topics after posts on AnandTech pique my interest in a certain subject.
And while trolls are some of the most well known members here, there are many helpful and knowledgeable users. It's a great place to ask questions, though you will get a lot of joke and rude responses from time to time on ATOT... which is fine, since it is Off Topic, after all.