Website owners,
In checking on URLs to know whether they are suspicious or malcious, we use a lot of scanners and sources. Just think of: URLVoid, Sucuri, soswebscan, virustotal, urlquery.net, unmasked parasites, google safeweb, M86 security, wepawet, comodo’s siteinspector, etc. etc. We have seen these scan report results appear and commented upon here in the virus and worms regularly.
Also you could check valid HTML against: http://validator.w3.org/check?uri=
and here: http://tools.pingdom.com/fpt/?url= (to check for weird browser requests) - use these next to a urlquery.net scan,
polonus