Steam collects a bunch of statistics on people using their service, and I suppose it means that someone can go through them and compile interesting figures.

Here's one such compilation:
http://arstechnica.com/gaming/2014/04/in...lar-games/

Main charts of interest:

The owned/unplayed stats are unsurprising - it's easy to get caught up in the sales they have.

(I bought Bioshock Infinite while it was on sale some time ago and have yet to play it..)

Football Manager as addictive as ever, I see..