Endless. The benefits are endless. But the main reason is that it's Yours. You have total freedom to do anything you like with your blog, it's your information on your server space that you own. It's easy to adjust and customize, easy to save and is hosted on your domain name, which is easier for people to remember.
You do not have to adhere to anyones rules about advertising and search engine optimization. You do not have to worry about losing your information, getting locked out of your account or forgetting your password. You have access to every single file in your blog's install.
There are a few available blogs for install within Fantastico. Fantastico is a wonderful collection of useful open resouce software that comes free with most hosting accounts that have cpanel (and other various types of backend user account administration) This also means that in addition to a blog, you can install all types of useful things for your visitors. It has a wide range: forums with polls & surveys, image galleries where your members can upload their photos and artwork. Geeklog where others can add their own content. Classifieds software (useful for link exchange) Your choices are automatically endless of the tools you can put on your blogs domain.
If you can navigate your way around html and php, you can control every aspect of your blog, and you can host any content you wish. By editing the template and images, your blog will be as unique as you are, not just another look alike. Editing a template can be as easy as changing the header logo image (which will be discussed later)
Free themes (templates) plugins and addons make it VERY easy to customize your blog. You can control your blog in many ways such as with a plugin that lets you run your blog in the opposite order from oldest to newest, AdSense plug ins, easy video coder writers and much more.
Search engine optimization is easy to do and with your own domain name that includes your keywords, it's even easier for the search engines to find you.