I think some people want to blog without it seeming like one big advertising. Sometimes I read articles on startup blogs and think "why are they even writing about this" until I get 2/3rds of the way through and realize I'm reading an infomercial.
Seriously, just put your product link at the top-left (like OP says) and throw the tagline right next to it. I'm not going to be offended that I'm reading a branded blog.
