I recently had a look at my Raptr play summary foir 2013 and it threw up some intriguing results. In first place with 75 hours logged was WWE '13, followed closely by MGR: Rising with 73 hours (take that, 'it only lasts 5 hours' whiners :)) and Dragon Age: Origins with 67 hours.
I know I played a lot of WWE but I had no idea I'd played it that much. I was also puzzled by my rarest achievement being Gunslinger from Metro: Last Light. All you have to is kill at least one enemy with every weapon which wasn't exactly hard so I can't imagine why this one is considered rare.