It would be a good thing, but Apple really should be acquiring TeleAtlas or Nokia instead.
I say it would be a good thing because Waze maps and editing not only need additional structure and control, but credibility and reliability. Right now, pretty much anyone can add placemarks, redlight camera locations, or whatever and have them locked. These may or may not be accurate.
The added injection of funds from Apple will definitely improve things as far as crowd sourcing. Right now, Apple is lost when it comes to traffic updates. As far as the accuracy of map data goes, Apple default maps are still more accurate than Waze in my opinion. I suspect this will always be the case unless Waze improves upon their map verification process. Waze should look at Google and how they handle the editing of maps and POIs, etc. It's done by their peers, not by just one person alone. Just my 1/2 cents on the topic.