VGChartz has gathered the pre-order numbers for the PlayStation 4 and Xbox One. The latest data is up to the week ending August 24, 2013. This includes the week of Gamescom, which set a record for biggest gaming trade show in Europe with more than 340,000 visitors. The pre-order numbers are for the US only and give an estimate how each console is doing about three months before release.
(NA region only.)
Update PS4:X1 ratio is 1.7:1