As I am in a situation similar to yours - still waiting for a decision - I like to make some suppositions.
I think "diversity" is really important for any MBA and especially for a top one. So, I think they work with buffers. If you are an indian IT guy (sorry for the cliché), you will be judge on your application and you will fail or pass. If you pass, your application will go in a buffer where other super smart IT indian guys are and then when the buffer is full, you will be compared among your peers in that group. So that, at the end of the day, your application is delayed because they are still trying to figure out if you are the best of a category or still waiting to find more applicants like you (in order to compare you with similar profiles). So if you are still waiting, it is perhaps a good news.
The other supposition is that the person sending Ding emails is too busy.