The article does not take into account other activities that have taken place the last few weeks such as Mt.Gox stopping all withdrawals that triggered a panic nor does it take into account governments like Russia stating that Russian companies should not use or accept virtual currencies.  There's been a LOT of negative press lately, and it is a very dynamic environment with a lot of variables.  Just attributing a lack of increase in value because Overstock started accepting bitcoin is like saying the ruble is going to increase because Overstock starts accepting it.  It doesn't (and shouldn't) happen.