Often when I am searching for things online I will stumble onto blogs to find what ever it is I am looking for. Since blogs have become so popular I think it is a necessity for every website, well most at least! If you have a website that is mainly an E-commerce site for dog clothes or whatever. You should set up a blog about hmmm… dog clothes. This will help your site with content for the search engines to search for and give your visitors a good reference for any questions they might have. Most E-commerce stores are a couple of pictures and a small description. Adding more content will help you get more natural traffic and increase your revenue. If you could incorporate your shopping cart into the blog you  will have the best of both worlds. I think one of the main reasons why blogs are becoming so popular is because they all are linking to each other to help increase their pagerank. Most sites are reluctant to do this for one reason or another but I can guarantee you that it is better to trade links with related sites like all the blogs out there are doind then to stand alone. What ever blogging script you decide to use is your choice but of course I think Wordpress is the best out there!