I don’t like to just link to stuff, but outsourcing choice at 37 signals is worth linking to. The post talks about designing interfaces with fewer choices. Really, the interesting thing here is Barry Schwartz and his book, The paradox of Choice. The paradox of choice being that having more choices makes you unhappy. Well, there is more to it than that. The New Yorker has a good summary of the book.
I watched a bunch of google tech talk presentations a few months ago. By far the best presentation was Barry Schwartz explaining The paradox of Choice. This video is worth watching.
I think these are important ideas in the quest for extreme simplicity.