I\'ve just upgraded my app to run on the new iPhone5 simulator, however when I try to build it for my iPhone 4S device, I get this Apple Mach-O Liner error.
Update to Admob 6.2.0 or later.
See this post: http://googleadsdeveloper.blogspot.com/2012/09/migrating-to-admob-v62-for-ios.html.
Also, include the AdSupport framework and remove the -all_load flag. You've got to use the -ObjC flag however.
This works for me, finally!!