Also, is the nVidia GTX 460M graphics card the best card on the market at this time??
No, the performance crown right now is split between the GTX 480M and the HD 5870. The 460M is between the 5870 and the 5850.
I have a slight bias towards Sager since I own one, but the Asus G73 would give the best performance if all else aside from the GPU were the same.