Academic blogs can serve different purposes, such as helping to promote your research, brainstorming platform, to engage with policy issues or with the general public directly, to talk about personal experiences in academia, to advance a particular field of study, engage with other academics. Whichever, purpose you chose, you should be prepared for opening up your thoughts and research to a wider audience.
WordPress.com or WordPress.org is the most popular blogging platform because it has an extensive library of settings, plugins, and features which let you customize your website the most out of all other blogging platforms. However, you can also use Blogger, Tumblr, and Medium, as alternative platforms, which can still help create an attractive platform for your digital content. Whichever of these programs you chose make sure to add plugins that will allow you to feature videos, photo gallery, audio, etc. These features will make your site more interactive and greatly enhance the feel of your site. WordPress has the most comprehensive list of plugins, which you can find here: WordPress plugins library.
Other Useful Sites
a. Slideshare: Could serve as a good medium to upload presentations, academic research, etc. It also allows you to have followers.
b. YouTube: Once opening a Youtube account, academics may be interested in posting videos on to the CitizenTube section of YouTube. CitizenTube is a special YouTube blog devoted to chronicling the way that people are using video to change the world.