Recommend content is advisable for E-commerce bloggers. For e.g. Recommended books. A buyer will want to know what more is there in store for him/her.
Image speak - A lot of bloggers tend to ignore this, but the images on your blog speak a lot for what you write. Use good quality images and make sure they express your written stuff in utmost simplicity yet precision.
Tutorials: For Business Blogs, have tutorials that teach your customers how to use the product/service, what are the features of the product/service and keep your customer views open for them to read.