Depends on the stock, and how steam is spending their bitcoins, but the BTC is going up so it won't affect the forum market I guess.
Steam doesn't accept Bitcoins directly, they use a 3rd party service, I think Bitpay, to process the Bitcoin payments.
As far I know Bitpay just dump their bitcoins as soon they receive them
Nope, people here on forum want things for something between 50-60% discount and paying full price is out of question. if Steam is not willing to give away half of the price people here won't be interested in buying directly (I'm not even sure if steam still takes BTC...)
you were living all the time under a rock to not know that steam offer up to 75% discount, in concomitance with festivity such christmas, halloween etc...
and yes they still accept bitcoin, via bitpay, you just need one confirmation and your order will be delivered without problem
the times I used them I needed no confirmation