HuskyPup - 10:56 pm on Jul 30, 2012 (gmt 0)
Just drop a cookie saying the user prefers the full site, then check for the cookie before you redirect. Simple, easy to implement and works 100%.
Definitely not 100% when users have cookies disabled like me...plus I have no idea how many others.
Even AdSense cannot differentiate accurately between desktop/tablet/smart phone.