There are a lot of new well-financed news hubs starting up. I have a suggestion on how to increase your flow, and overcome at least some of the barriers to entry erected by your more-established competition.
Identify people on the web who are influential linkers.
For each, recommend a set of feeds they should follow on your new site.
Make the approach carefully, as you would with a PR campaign.
The reason is one that’s often overlooked. While RSS isn’t “mainstream” the people who push links through the main stream do use RSS to keep up to date. I am one of them. I have feeds already for all your competitors. It’s good for you if I add your feeds to my flow, I can’t link to your great stuff if I don’t know about it.
I know this is selfish. I want you to do my work for me. But they’re your links, your stories, and you have a hill to climb, and I’m happy to help if you meet me half-way.