Things that irritate me about them, rather.
First, if you're going to copy and paste an article from another, very popular tech blog. At least give credit. I randomly see dirrect copies of blog posts from gizmodo, for example, with no credit.
Also, if you're posting images? Give credit. it's not your work, and the original creator, whoever it may be, might just want to get some of the feedback that's being posted about their work...I've repeatedly seen images saved directly from deviantart.com, among other websites, and uploaded on blogger.
And Captcha. Why the HELL do people use it? it's irritating, and makes posting comments and feedback on your blogs not worth the effort, most of the time.