Reddit.
Not a fan at all of reddit's layout. Everyone always tells me I'd love it over there, but I can't get over how terrible the layout is.
It just annoys me how it sorts information. It's essentially replaced the standard phpBB or SMF etc. internet forum, but it's such a colossal step backward as far as organising information in any meaningful way is concerned. It's essentially the Twitter of forums; tiny repetitive messages that get spammed over and over again.
I don't lurk any really big subreddits, but even the ones I do are just flooded with the same shit over and over again. Any time someone has a thought or question about something, it gets its own thread - completely unlike a real forum where we have threads to organise all the similar thoughts and information together. Then if a subreddit dares to attempt to do that and creates a megathread to try and clean the sub's pages up because hundreds of people keep posting the same bullshit things every single day, everyone complains and downvotes the hell out of it, the mods, and anyone who posts in support of the megathread, because apparently megathreads are stupid.
If it weren't so popular I would never go there, but for a lot of topics it is unfortunately one of the best sources of news and information, or even discussion....if you can be bothered to sort through all the BS for that news, that information, or to find that discussion.