Now that Google Apps will no longer have a free account, will we need to pay Google to be able to use custom domains on Google App Engine?
[update 2015-09-28] Now Google lets you add custom domains and setup SSL without the need of Google Apps. For details refer to here: https://cloud.google.com/appengine/docs/using-custom-domains-and-ssl?hl=en
Update...all the free lunch are over!
The announcement itself is here - https://groups.google.com/forum/?fromgroups#!topic/google-appengine/jC_K-YlmXhM