too smart a bird; diff between "will" and "is going to"

too smart a bird
(AUE: by John L. )


diff between "will" and "is going to"
http://groups.google.com/group/alt.usage.english/browse_thread/thread/25d0175e8fcb0e93#
http://groups.google.com/group/alt.usage.english/browse_thread/thread/a5cf094689ce57da#