Recent hacks
This may not have anything to do with the websites's content. For example, several large hosting services have been recently attacked from China. A line of javascript was inserted into pages, calling an Adobe Flash exploit. For example:
<SCRIPT src="Sputnik_files/avqwb_cn.swf"></SCRIPT>
I recommend running the Secunia scanner, since recent hackers seem to be targetting Flash, Quicktime and the Java runtime.
http://secunia.com/vulnerability_scanning/online/