Niche Blogs: A Couple Interesting Ideas

A few days ago, I had an idea. I know that many site owners republish content found on sites such as EZA, and from what I understand, this is accepted and even encouraged as long as you do it properly, such as including the author resource box.

I thought of something, and I don't know if people are already doing it. What if someone took a bunch of articles on a very specific subject and used just those for their site content? What if they had an exact match keyword in the domain and everything? Would it be considered ethical/not against TOS to do this? The advantage would be that instead of having an entire directory full of all kinds of various articles, you have one very specific set of content for a niche.

Well, maybe a day or two after I had thought of this, I get an email from Viper Chill (who I just recently found out about), talking about the concept of having people guest post on your niche blog and just using that as a content source (I'm guessing this is opposed to cross-promotion). It's a win-win, because those people get their work syndicated, and you get more content for your site.

Either idea seems interesting to me, though I probably wouldn't mess with this stuff as I have a large project on my plate right now. But, I was wondering what others would think. Wouldn't there be a huge SEO advantage in both cases?