So an official announcement must be happening soon. I don't think retailers pre-empting with a $50 cut means Sony will cut by $100. But it's possible that Sony has dropped the wholesale price by more than $50 to give retailers some extra margin to play with even after the $50 cut is made official. I don't think Sony wants, or needs, to force console prices down below $300 just yet. Save that $299 tipping point for 2016.
I say MS will respond with a cut to $299 for 500GB skus and $349 for 1TB skus. They might wait until after Halo 5 ships so that they get to maximise the revenue from the Halo 5 LE console. But early / mid November MS will do a reactive $50 price cut. Xb one cannot compete with PS4 at the same price, even with Halo.
“The fundamental cause of the trouble is that in the modern world the stupid are cocksure while the intelligent are full of doubt.” - Bertrand Russell
"When the power of love overcomes the love of power, the world will know peace."
Jimi Hendrix