So, after more retailer accepting BTC is indeed good news in the long run, as it gives more perspective for BTC adoption. In the short run, it is a high pressure on the price, more big retailers means purchases with BTC , BTC being cashed out in $ immediately. Long story short, when the supply increases, prices will fall down for another equilibrium. At 300 if it gets there, will sure be a place where the market would find attractive to purchase BTC if we complete the .
All in all, more important retailers will bring more awareness of BTC and by developing more hardware and soft are infrastructure for BTC users will mostly be the best for the BTC community on long term.