However some of the website owners may not like you're downloading the content of their articles and hosting them elsewhere. There is a great army of spam sites that will just watch http://pingomatic.com/ and scrape each new entry. Then they will on host it on a splog and stick adverts up. Which gets website owners annoyed.
Trouble is Google might not realize which is the main site and won't get the page rank or the visitors don't come to their site but an alternative. They'll get annoyed as they won't be able to monetize them or see who is reading the page through analytics.
So you may want to set up a DMCA page and abuse email address to stay on the right side of the law. Also a robots.txt which denies Google and Bing from crawling the pages you downloaded.