The fact that you are even asking the question points to WordPress for your initial, and possibly ultimate solution, since WordPress was conceived and evolved to serve the purpose of delivering content.

However, don't assume that with WordPress you'll be ready launch from day 1, as some have suggested. If this is a serious business, at the very least, you will need to plan and structure your site's architecture, curate and configure and test plugins and theme/frameworks, design and configure forms for landing pages and newsletter capture, pull in and curate feeds or submission forms for all these articles, seo strategy and automation, establish contributor roles and editorial workflows, widgets, sidebars, conditionals, and customize the backend to simplify and secure all of the above. If you are serious, you may also need to build custom post types, meta boxes for custom fields, and custom templates and search forms to display them; Then there are advertising systems, social media inflows outflows etc... And maybe you'll even decide to build an a mobile app and use WordPress to power the data, users, and backend.

If it's starting to sound like custom development that's because that is exactly what it is. But by the end you will also know what the limits of WordPress are and know enough about your audience and the development of sites that if you do decide to go with something other than WordPress you will be better for it.

If there is one thing I've learned in 7 years of WordPress development it is that every site is different and WordPress is a powerful and complex platform—not necessarily a simple one (to develop in).