This is done to hide the original URL and make it harder for scanners to identify the malware.
Not very common type of malware. Some URLs:
http://bit.ly/QTYgXYYZ .. a few more..
Those are often used to redirect the browser to spammy sites. However, since this is a generic rule, the malware can change from site to site.
Affecting: Any web site (no specific target).
Clean up: Nothing specific.
Last update: Aug/2012