actually i think that it should affect price of bitcoin, but not by much, maybe by one or two dollars only as there are lots of people that use bitcoins and steam but that's still not enough
I was hoping it would increase the price by a lot, but that did not happen, which is sad.
Having a big company like steam trusting bitcoin, must mean something, at least for PR purposes right.
I was really hoping the same to but seems theres no effect of price but i all i see now is increasing user of btc i see now wandering in any sites and mostly here. But in some other instance steam acceptancr have good effect for bitcoin since he give exposure to bitcoins and company would provably see's it and may can gain more popularity and acceptance.