E-commerce bloggers must carefully write keeping their audience in mind. Everything you post on your blog will speak for your product or service. Your interaction with bloggers in comments and otherwise will give you a direction.
Put advertisement but make sure that your blog visitor doesn't get irritated when ads pop up one after another like a flood.
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.