If you want to use the Android SDK (this includes additionally Google APIs), you have to agree to this license: http://developer.android.com/sdk/terms.html This is also needed to release your App in the Play store.
Someone has argued source.android.com should be given a different name, similar to chromium and chrome. I think that would clear things up, too.
People who fork Android wouldn't really benefit from offering a separate SDK anyway. They would want to take advantage of the existing app ecosystem and preserve compatibility, just like Amazon is doing with Kindle Fire.
If you want to use the Android SDK (this includes additionally Google APIs), you have to agree to this license: http://developer.android.com/sdk/terms.html This is also needed to release your App in the Play store.
Someone has argued source.android.com should be given a different name, similar to chromium and chrome. I think that would clear things up, too.