The way I figure, this first announcement could have been about MyGM upgrades, featuring something like the ability to import Diamond Kobe into your MyGM once you've accumulated 17,753 points in Virtual Currency, or new GM/Player soap opera cut scenes.
Instead, the MyLeague reveal seems to insinuate at least a partial return to off-court simulation, control, and realism. After 2K13 and 2K14, I think a lot of people were wondering if it was time to come to terms with NBA 2K being a game featuring authentic on-court play but VC-driven, awful-story-mode ridden, lowest common denominator unrealistic interactions off the NBA hardwood.
Personally, I was prepared for every mode in 2K15 to involve VC payments and an emphasis on always being connected to the internet without the ability to save locally for the foreseeable future. Instead, 2K seems to have gone in the direction of classic 2K in regards to this MyLeague revelation. We'll have to see how it actually plays out but it seems like a great step in the right direction - and though it's a return to how things were before in many regards - it's a welcomed return.