IMHO XBOX360 came out a year ahead of its competitors, its devkits were in the hands of developers long before that. It has been the defacto standard as far as HD gaming is concerned.
Multiplayer games and FPSs were popularized by xbox/xbox360 and XBOX live is what everyone else is trying to beat/emulate. So for HD gaming XBOX360 is the standard (for now).
As far as which company has executed well this gen is concerned there is no doubt that Nintendo has done extremely well. Regardless of the fact that there are less highly ranked games on Wii it has managed to sell a huge number of games.









