Few weeks ago I was contacted by Gaby Becker with some issues for the GCM module I maintain.
I was happy to help, and was even more happy when she wrote a post in her blog describing the whole process.
Currently the implementation described actually uses a combination of GCM with the Push notification module, but the most important thing is that it works, and their Webgrrls Events application now got "push notification" capabilities, backed by standard Drupal modules.
My plans are to continue enhancing the GCM module capabilities, while releasing an Android SDK which will make it simpler for developers to integrate between Drupal and Android.

I hope this post will be useful for others, and thanks again Gaby for the detailed information.
Regards,
Shushu

Ralates to: Drupal PlanetGCMPush notificationAndroidDrupal