I would love to see Bing return as one of the providers of POIs for Waze. It used to be listed next to Google up till last summer, but now you are stuck with basically only Google for results as Yellow Pages, Yelp, and the others rarely provide help.
The Bing results complement Google's nicely, as many times Bing has more up to date info than Google, and vice versa. Recently I was looking for a Wells Fargo ATM, The Google results wanted me to drive 50 miles away, while Yelp and YP had no hits. I fired up Bing maps and did a search, found an ATM a few miles away, then copy pasted the result back into Waze to get there. If Bing was listed as a search option I wouldn't have to jump through hoops to get where I need to go. Yesterday I dealt with a similar situation, where Waze couldn't find me the UPS Store in Ardsley, NY using any of the built in providers. It kept wanting me to go into NYC to find a UPS store, while Bing Maps was going to get me there without any fuss.