Yes, I read them. But then again, my reading-list isn't huge, so there's rarely a lot of notifications to go through.
As for my own wall-posts.... I haven't made many of them. I post thank-you pictures when I cross big subscriber-numbers (100+ subs and 200+ subs) and I might do an announcement this week regarding the con I'm going to this weekend, but I tend not to do chat-posts. People can talk to me in the comments of my comic!
I'd appreciate the option do choose which notifications I got, though. That would clear out the clutter, especially if I build up a bigger reading list.