User Blogs

I am creating a community site where I would like all user to have the ability to create their own blogs, and these blogs will be posted to a feed on the home page of the site, with very specific catagories and tags. After searching high and low I found WPMU and saw that some of your buddypress themes had this option, So I downloaded the magazine theme and installed it. On the demo of the theme their is an activity section called blogs and it appears that the blog posts have showed on the front page as I would like, however on my instaled theme this option is not there, could you let me know how to activate this, is it a plugin?do I need to install multi site or can this just be created within buddypress? Thanks