How is Reddit simple? By my count they have 40+ navigational buttons on the main pages and each story has 6 buttons (in one form or another) [1]. Reddit absolutely overwhelms me with places to click and gives me no sense of it being nicely organized (as opposed to Craigslist which I think feels very orderly). Amazon feels a lot like reddit to me, but I mostly only need to use Amazon's search bar, so it's ok.
Reddit is certainly not a design with simplicity in mind. The sheer amount of links and navigation in general is completely overwhelming. I'd say it's rather a poor design.
1. http://imgur.com/wVO2JUI