NBA 2K11 isn't just putting a new coat of paint on a reliable model; this year the game will feature advanced controls that strives to deliver more distinctive moves to players' shooting, dribbling and driving repertoires, with corresponding animations.
The advanced controls are an option in the game, meaning you can still play with its classic control set. You can read up more about the new command structure, what went into it and why (note, kill the volume on your computer while you read. For some reason the audio from this video will run even if it's not playing on that screen.)
I can say that, based on the animations here, there is a lot less - practically none, really - of the popping in and out of animations you've seen in the past. Visual Concepts has said it added a ton of new transitions, shots and other actions to make the player movement more fluid. What they've shown so far backs that up.
NBA 2K11 is out on October 5.