I think launching a Google Maps alternative based on Bing Maps or similar should be a great opportunity for plugin developers to gain a huge amount of users. I don’t think everybody’s interested in all Google Maps features, but location and street names. For example, a “Contact Us” or “Where to find Us” page, present in almost every corporate website, just need to show a little widget with the store location and less more.
I definitely would use an alternative maps plugin instead asking all my clients to get an Google Maps account, enter billing details, and provide me their api key just to continue showing a maps widget.