As far as I can tell that particular vulnerability isn't a CSRF at all, it's an insecure JSONP endpoint[1]. The original author is mistaken.
[1] http://homakov.blogspot.com/2013/02/are-you-sure-you-use-jso...
CSRF attacks are very real, but the impact is generally taken into account before calling things a "vulnerability".
e.g you can have a SQL injection that's not a vulnerability because the input passes through a substr($_GET["id"],1,1).
http://archive.oreilly.com/pub/post/gmail_exploit_contact_li...