Multi-user blogs will help users to contribute news and industry information with multi-user capability. Here is the list of Best Multi User Blog Software.
WordPress MU : Multi-user version of the famous WordPress blogging application. WordPress MU underlying software that powers the WordPress.com, where it serves tens of millions of hits on hundreds of thousands of blogs each day.
b2evolution : A medium scale CMS centered around the Blog concept, fully featured with multiple blogs, content/presentation separation, full user management, full internationalization (i18n), workflow management… and extending towards features normally provided by Wikis, Trackers or hierarchy driven CMSes.
Lyceum : A stand-alone mutli-user blogging application, designed for the enterprise. Utilizing the fantastic, intuitive WordPress blogging engine at its core, Lyceum enables stand-alone, multi-user blog services for small and high-volume environments. Lyceum is GPL-licensed, under active development, and free to use.
You might want to checkout Blogs.mu which allows your to setup your own WordPress based blog community, simplified WordPress MU.