Target sent someone an Xbox One early (which got banned I guess, goto GAF), and he jotted down a bunch of game sizes. NBA Live 14 was shown to be 9GB compared to the 43/50GB of 2K14.
http://www.neogaf.com/forum/showthread.php?t=711802
TBH, I am kinda hoping I can grab a copy of Live early through all the launch insanity. Especially since we aren't getting a Friday demo anymore. If I fail, I am definitely going digital on this sucker. Only 9GB? I'd take that for the benefit of welding the 2K14 disc in the console and never having to take that out while still playing both games.