I have recently changed from adMob 6.4.1 to Google Play Services rev 15 and have just received notice of a new crash report that I do not understan
adMob 6.4.1
rev 15
This issue was introduced with the latest release of the Google Play Services (v4.3) on the android devices. Google is aware about it and it will be fixed in a future version (not the next one...)
https://groups.google.com/forum/#!topic/google-admob-ads-sdk/sePctoDJbRg%5B101-125-false%5D