His writing about truisms and plugging StackOverflow started to become too frequent for me. I can't help feeling that such posts are only written for their advertisement value. I expect some sincerity from blog posts.
I'm not sure why you doubt his sincerity. Stack Overflow is where he's spending most of his time these days, isn't it? Why wouldn't he be mentioning it in most of his posts? It seemed appropriate for this post. What would constitute a sincere blog post?