I like how the quarter breaks don't take you to a white screen where you feel totally removed from the game, but stay in the arena, similar to Live 99. I didn't buy Live 2003 so I don't know if they did this in that version, I think they did, but I wasn't about to pay money for that game to find out.
From the
gamershell previews, the court looks tighter and more compact, which is not necessarily a bad thing. I think real basketball courts are like that; from the Live 2003 screenshots the court seemed too big.

Pics from
gamershell
I know this isn't the perfect comparison, but notice how the 2004 court seems more compact, whereas the 2003 court seems huge. I know the zoom level of these two pictures probably differ, so you might think that that is why the 2003 court looks bigger, but the overall size of the court would become smaller in porportion to the players if you zoom out.
The fact is that the court for 2003 might have been a bit too big, I think I will prefer the more compact 2004 court because it might be closer to reality.
But on second thought, maybe the camera angle is different, not necessarily the court. Either way, hopefully we will find out for ourselves this week.