Instead of competing against other products and services, why not allow them to be PART OF (feed info into) Waze? Plugins, if you will.
Case in point: http://www.youtube.com/watch?v=sOyhnwA6MQo
Escort Live is a social driving program for people who use Passport Radars. Wouldn't it make more sense for everyone ("them" because they'd be able to enjoy Waze and its massive user database, and "us" because we'd get the real-time radar info?) if Escort Live was available inside Waze?
Waze is great because it's so clean, so I understand not wanting to have other data services "clutter up" the experience, so perhaps if a user wasn't "subscribed" to a service, then they wouldn't see the data in that "feed" in the first place.
There are two highly rated suggestions covering this: waze api,and intents. Vote for those