To make posts more interactive, if you occasionally use videos in your blog OR if you are a regular video blogger, then a Video Sitemap can help search engines spiders (like Googlebot-Video/1.0 etc.) in better finding your Video Content (including hyperlinks), that may not be discoverable by their Normal Crawling Process.
If you are running a self-hosted WordPress blog (You are the Administrator!) and multiple authors are writing content for you, then some of you may definitely want to setup an advertisement revenue sharing system, so that every author gets 100% of the revenue generated from the articles they have written!
Backing up your WordPress powered Blog regularly is very essential as disasters like Coding / Installation Errors, Hacking, Server Hard Drive Failure, Data Center Network Connectivity Failure etc. can occur anytime! If any of these occurs, either your valuable data will be lost or your blog will be offline for hours.