The $100 price difference will make a HUGE difference for the average American video gamers (not to mention no DRM, no restriction on used games, no required online, etc...).  Previously, although I was confident that PS4 will outsell Xbox1 globally, I didn't think PS4 would outsell Xbox1 in the US.

Sony absolutely trolled MS at E3.

MS has lots of catching up to do such as price drop even before console release day or removing required online or removing used game restriction.