I am cautiously optimistic about the 2k14 next gen teaser trailer, but there is little to no actual gameplay there. Graphically, it was something to see (except for Lebron's mouth at the end.) Gameplay wise, I saw nothing in the demo that said it was actual gameplay. Devs can do a lot of things with a modelling engine that the game just can't replicate.
In the end, it will always come down to the gameplay. I can put up with accessory errors and incorrect jersey colors as long as the gameplay feels like it should. Right now, neither company has shown what the game will look like when actual people are playing it on next gen.