I am a pretty picky reader. I always have been with real books, but I didn't used to be with fanfic. I used to read just about anything, especially if it was about Brian, but I also think there was more to choose from back in the day - more websites to explore, more of the kind of stories I really enjoyed, the dramatic tearjerker and suspenseful stuff. But my standards for things like conventions and presentation were also a lot lower. I knew and followed the rules for paragraphing, dialogue, etc. in my own writing, but it didn't bother me as much to read stories that didn't.
Nowadays, maybe because I've read so many stories, it takes something special to hook my attention and suck me in. Besides the storyline appealing to me, the writing has to be good - I won't waste my time on poorly-written stories. I don't have as much free time (or maybe I just have more distractions), and usually I'd rather spend the time I do have for fanfic trying to write it, rather than read it. I still read it when I find a story I want to read; it just doesn't happen as often.