Well, according to this post, everyone who was technically knowledgeable about Bing has left.
That implies that there will no longer be any relevant technical progress, any more.
That implies that there will no longer be any relevant technical progress, any more.
That is at least anecdotal evidence that things are progressing in some way or another.
Why would you want a predictably wrong answer, you must be a manager.
How do you know it doesn't go back to showing irrelevant results on the 28th?