Hmm. Interesting. The work actually involves summarizing books, scientific papers, websites, and so on. It's not a place to post your unpublished articles or short stories!
The income derives from Google AdSense and other pay-per-click advertising on the site. This will presumably be split three ways - Google, the website itself, and finally the author, so I wouldn't expect to make a fortune from it.
On the other hand, if you enjoy writing book reviews and such like, it may be worth a shot. My top tip would be to review current best-sellers, as this is the type of book most readers (relatively speaking) will be interested in.
Nick GM