I like many others in the NPD prediction thread predicted the X1 to beat the PS4 in March due to Titanfall and price adjustments in retail. For example here was my prediction (now very wrong).
[XBO] 380K
[PS4] 350K
[WIIU] 95K
[PS3] 110K
[360] 130K
[3DS] 150K
[PSV] 50K
But then something odd happened and VGC actually overtracked the X1.
XB1: 258K/4 February
64.5k a week
XB1: 311,00/5 March
62.2k a week
Did Titanfall and bundling and price adjustments help?
PS4 for comparison
PS4: 280k/4 February
70k a week
PS4: ~371k/5 March
74.2k a week