In-text advertising has to be the most annoying form of marketing used in blogs. It is even worst than paid posts. I can ignore paid posts but sometimes the in-text ad links look like real links. Sometimes when I move my cursor over a page to check something the ad link is triggered and this annoying pop-up obscures what I want to see.
There is another problem with these ads. Quite often they are unrelated to what is being blogged about. Have a look at this screenshot:
According to the ad you can buy 'your blog' on eBay. The ad looks silly and the whole advertising aspect of the blog loses credibility.
If people want to 'monetize' their blogs they are better off producing great content and finding a sponsor.