I think someone said that Sony could manufacture 1 million a month. So if they started in late august (let's say they didnt make any), they are going to struggle to get 4-5 million consoles made between now and end of december.
So i dont think its likely. Something that I think:
I think the PS4 will sell very well between launch/end of year (it will sell more than wii-u did last year)
I think Wii-u wont sell much over Christmas and the games that do release will not have a big impact
PS4 will pass the Wii-u sometime next year... probably early (march)