I purchased both. So far the Xbox One is getting more play time from me. Here is what I have played on both.
XB1:
Dead Rising 3
Ryse
Lego Marvel
Killer Instinct
Forza 5
PS4:
Battlefield 4
COD Ghosts
Knack
Killzone SF
AC Black Flag
Outlast
Injustice
Best Looking Game:
RYSE
Favorite Game:
Dead Rising 3
Game Most Played:
Battlefield 4
Most Disappointing Game:
Killzone SF
Overall better experience so far:
Xbox One
I never thought I would say this, but the Onenis my favorite at this moment. It could change later this year or in the future but the overall package is better on the One.
Games im most looking forward to...
XB1:
Titanfall
Thief
Destiny
Halo 2 Anniversary
PS4
Infamous
The Order 1886
Dying Light
MGS Ground Zeroes
Some are multiplatform but these are the systems I'm getting each for.
Sorry for the long rant. In the end, for now, the One is my favorite.