Blog thoughts

Perhaps I'm missing something, but in many respects these blogs seem much like any other websites - at least from the user/reader's point of view. You get on with some better than others, finding their tone, presentation, content, etc. more or less helpful/engaging depending upon who you are and what you're looking for. I guess it also depends on the purpose behind them. Are they for the blogger's own interest/ego (ok, none of those actually referred to in the instructions, but you know the sort I mean), or are they designed to make a contribution, to help others. I liked the Jane Knight one enough to bookmark it, but wonder if it's all as it seems. Lots of ads and links to software packages... how much does it cost to have your site or software featured on a blog like this?