I'd like to create a site with the following features.
1) It would look similar to CNN where the top 10 or so stories from all are listed at the top of the page and then further down on the page each 10-12 are listed with the top 2-3 articles under each category.
2) I'd like it to subscribe to the RSS feeds of certain blogs of my choosing and then automatically add the posts to my site as they become available in the RSS feeds.
3) When posts are added, I'd like it to look at the tags of the posts in the RSS feed. If a tag matches one of the on my site, it would be added to that category. There would be the potential of adding a post to multiple .
4) I'd like people to be able to recommend a blog's RSS feed to add. I would have to approve it. I don't want people to be able to submit individual articles/posts.
Can someone tell me if each of these features is possible? And if they are possible with existing functionality or if I would need to have someone develop any of them?