I don't have the education to have a discussion with any of you on the algorithms or statistical distribution; but I would simply like to relay to you some personal observations. Firstly, thank you for the article - it is a subject I have been thinking and talking about (without the science you include) for some time to all that would listen. Years ago, when I first saw recommendation systems on the net or aggregation websites (/. or digg or reddit) I innately felt that these systems would provide "gravitational" pull to certain subjects or objects and lead towards a monoculture. I still feel this way today. Sure there are a number of discovery systems being introduced but even these ones allow for weighting and as such are likely destined to become echo chambers. I suspect that these systems are creating islands of interest and at the same time decreasing mobility (from one island of interest to another). To make a long story short: it isn't the end of niche - but the dying days of serendipity. I personally fear this. For me "serendipity" is the mechanism by which "I know how much I don't know". It helps me to be humble about my understanding of the world, which in turn allows me greater freedom to explore solutions to problems (even in deciding that a problem may not be a problem at all). Does this mean that I am less competitive than those that quickly reach for the recommended tool and execute the recommended procedure? I suppose - yes. Thus, the individual needs to make a proper decision: when to ascribe to "common knowledge" and when to allow serendipity to place you in a some random location. Has this made my life better - I don't really know... but my gut instinct is that randomness is good, and needs to be actively preserved. Thanks again for the article.