Blog marketing is any process that publicises or advertises a website, business, brand or service via the medium of blogs. This includes, but is not limited to marketing via ads placed on blogs, recommendations and reviews by the blogger, promotion via entries on third party blogs and cross-syndication of information across multiple blogs.
Ads on blogs can be in the form of banners, text links, streaming video, audio clips, flash animation and even plain text. Most blog-based advertising involves payment in some way or the other to the blog owner. Owners of popular blogs will typically capitalise on their readership numbers via a combination of ad formats and Google AdSense ads.