Steam is accepting the bitcoin and that is not really known these days so that is pretty funny, the prices here on the forum are also much better so its logical that it will not really affect the market right now.
What price here on forum are you talking about? People selling games/keys on digital goods?
I think you can save more with steam discounts and promotions.
I disagree about this to be honest because of the fact that the games that are sold on here are way cheaper than on steam itself, you should take a look if you do not believe this.