For the Base-USA distribution, I've now removed WU-radar-inc.php, WU-radar-testpage.php from the distribution, changed flyout-menu.xml to remove the link, and changed wxradar.php to handle missing WU-radar-inc.php gracefully.
It has been a long-running script (first released by Tom of Carterlake 07-Jan-2008) and has been adapted over the years as WeatherUnderground tweaked with their website design. Now it's time to say goodbye -- they apparently want to focus exclusively on the WunderMap for radar display and that's not really adaptable to our scripting for personal weather websites.