Microsoft exec Gurdeep Singh Pall is speaking right now at the SMX Advanced search industry conference in Seattle, and host Danny Sullivan spent some time pressing for details on the company’s newly announced deal with Apple to integrate Bing into the Siri personal assistant in iOS 7.

Pall seemed to be doing his best not to make any news on this topic, but he did cite the arrangement as the latest example of Bing expanding beyond the traditional search box. And he pointed out that the more users Bing can reach, the better it will get, based on machine learning technologies that shape and improve search algorithms as more people use a particular search engine, creating stronger feedback loops.

“We are very excited about it,” he said of Bing’s integration with Siri.

Previously, Siri used whichever search engine was selected by users in their iOS settings, where Google is the default. Under the new arrangement, Microsoft says Bing will be used for all web search in Siri. The company declined to disclose financial terms of the deal.

Pall, corporate vice president for Microsoft’s Information Platform & Experience team, declined to comment when Sullivan asked if Microsoft is working on a Siri-like personal assistant for Windows Phone.

“It’s great to see speech take off, but the reality is that human beings are inherently multimodal,” he said, pointing out that it’s becoming technically possible, at least, to detect the dilation of a user’s eyes, or how a user is gesturing with their hands, and take those inputs into account in determining search results.

On the topic of Bing’s rising market share, now more than 17 percent in the U.S., he said, “It’s been wonderful. The team is super-energized. What it allows us to do with a respectable share of the search space, is pivot and use those assets in the different ways that I’ve been talking about.”

Much of that gain has come at the expense of Microsoft’s search partner, Yahoo, which has slipped below 12 percent market share. Yahoo CEO Marissa Mayer, the former Google executive, is reportedly displeased with the results from the partnership so far, but Microsoft has pledged to make it work.