Some answers to questions I had

Uses WebGL with fall back to server side rendering with tiles, they call it "adaptive rendering modes".

What for? "Unify on a single map provider with familiar, flexible APIs" (from WWDC slides).

  Free tiers
  ----------

  Mapbox
    web
    50K map views / mo
    50K geocode / mo
    50K directions / mo
    50K matrix / mo

    mobile
    50K monthly active users
    same requests


  Apple
    web and mobile
    250K map views / *day*
    25K service requests / *day*


  Google (new style $200 credit system)
    (this is too complicated)

    web
    $200 free credit buys one of:
    14K map views embed advanced, might be anything with search/directions/routing, including on mobile / month 
    100K map views static on web / month
    28k map views dynamic on web / month (this hurts)    
     
    mobile
    unlimited mobile map views (very simple kind)
    14K map views for anything interesting / month
    40K direction requests / month
    ~10K Places calls / month

That's the max for any one service if you only use that service. So you could use 20K direction requests and 14K dynamic map views for free per month.

Google Maps gets expensive quickly, 71K embedded advanced map views per month is $1000 per month.

  roughly
  Google Maps: very expensive 
  Mapbox: moderately priced
  Apple Maps: very cheap

Licensing...

Google is restrictive. Can't be behind a login, can't track vehicles/assets, can't embed in a web view on desktop, in practice can often not embed in an app on iOS.

Mapbox is famously open, you can do all the above.

Apple seems like they might be more like Mapbox, given their goals, but can't find any licensing yet.

If the licensing turns out well, this could very nice for cross platform maps.