Social media in general -- Facebook, Twitter, Instagram, Pinterest, etc. -- have made it easier than a blog to get your thoughts onto the internet, and the extremely social nature of those services and the instant feedback and conversation they encourage (the social part) is very compelling.

Even though the major blog platforms (Movable Type, WordPress, Blogger/Blogspot, etc.) had a social component in the form of comments, the big social media sites -- including Reddit -- took it up quite a few notches. People like the feedback and the conversation. Blogs can be much more of an island. Some like that, too.