Problem fixed.
Decided to follow steps here: http://codex.wordpress.org/Using_Your_Browser_to_Diagnose_JavaScript_Errors
Tested on IE, FF, Chrome - all same problem.
Added line to wp-config.php define('SCRIPT_DEBUG', true); Still fails.
Step 3 Diagnosis: In chrome saw this:
Uncaught ReferenceError: _gaq is not defined
Checked source and can see the new Universal GA code being used
Searched for Universal GA code snippet and found this:
http://www.astralwebinc.com/contact-form-7-wp-how-to-add-event-tracking-on-new-universal-google-analytics/
Updated Additional Settings to use Universal GA code snippet.
Fixed.
First comment on above also leads to this:
https://wordpress.org/support/topic/not-shown-message-was-sent-ok-if-tracking-form-submission
This was exactly my problem.