We posted a blog "Twittering Botnets" a few days ago which gave details of malware which receives obfuscated URLs from Twitter messages. This malware is detected as Downloader.Sninfs, This blog also made a prophecy that alternative sites could be used in the same fashion, this one has come true.
Downloader, micro-blogging and prophecy: http://www.symantec.com/connect/blogs/downloader-micro-blogging-and-prophecy.