My feeling on blogs is that they are all too often used as personal homepages or as online diaries which aren't always interesting or informative unless you happen to know the blogger. That having been said, there are some excellent ones. I have some great links saved on my laptop to blogs covering film posters, music I enjoy, quirky design and general silliness. A favourite of mine posts bad photoshopping in posters and adverts. Another is devoted to the cataloguing of fictional books within books. It seems to me that the best blogs are those with a focus.
Outside of personal blogs, is there a market for professional or institutional blogs? I think there probably is. For one, it is a great place to post "breaking news". For example, during the recent snowy weather, the Oxford Brookes blog was where I found out the up-to-date opening hours (which saved my girlfriend an unnecessary and cold walk). I have been very pleased to see the latest book titles, news (and, in some instances, special offers) posted on publishers’ blogs, and many authors (as well as non-literary celebrities) keep an online diary with thoughts and opinions, too. A blog would be a great means of keeping abreast of, say, the latest developments with the OULS Book Storage Facility at Swindon (new photos on the website, folks!).