ewt_pagename, because the Acoustic Campaign accepts the value of ewt_pagename if it is found on your tracked page.
If your web page is http://www.example.com/index.html?content=januaryupdate you can use a regular Expression to parse the URL and return a value of
index.html?content=januaryupdate. To do so, replace the line above in the function that contains **** with:
ewt_pagename = window.location.href.match(/[^\/]+$/);
If your web page generates a dynamic title with the query string, you can pull the page title and pass that back to the Acoustic Campaign. To do so, replace the line above in the function that contains **** with:
ewt_pagename = document.title;