Do not panick.
Because of some of the scanned url’s it has on it. Some not so well-informed WOT users take that as if the scanner is infected itself and is not. Or they are opposed to certain scan results (web rep issue).
Only if you would open the URLs marked red there in your common browser you can get infected, but you have to visit the link first and then open that up into a common webbrowser with off course is a very unwise thing to do. So actually same arguments WOT users have could be used against any malware URL list!
So actually the scanner is meant for the security aware and scanning the requests and repsonses in a sandboxed environment for safety. These folks are those that know where to cut and paste and where not and what not to click through somewhere els/or in a browser or scanner.
So that scanner is to be used only for scanning the code of sites for suspicious and malicious issues and never actually go to that particular site or visit that code.
See why we here consider it safe, especially in the hands of those security savvy that know what to do with it: http://www.webutation.net/go/review/urlquery.net
Also this scanner gives alerts for exploit packs and bot site requests, because it gives a detailed expose of browser requests and browser response. Others scanners do not have those alerts.
I would say glad we have it, and WOT users are only right as how far the scan results can be abused, that is all.