For years, email spammers have been looking for ways to encourage people to click on their links. And for years, Google has been a target. Why? Well, when someone sees a link that has google.com in it, people trust it. So over the years, Google URLs that redirect to other sites have been a target by spammers.
The most recent Google property targeted by such attacks is Google Reader.
A Google Reader Help thread has reports of such cases, with a Googler confirming it is an issue. Several people are reporting receiving email spam with URLs that look some thing like:
http://www.google.com/reader/item/tag:google.com,2005:reader/item/3c49b76cf8cb8ba0
Clicking on that URL would have redirected you to a non-Google site.
Googler, Roger said:
It looks like some spammers have taken a liking to Google Reader - we're currently trying to find the best way to limit this kind of automated abuse without impacting the experience of real users such as yourselves. Hopefully we'll have a solution that works for everyone soon. Thanks for your patience and understanding in the meantime-
So be on the look out.
Forum discussion at Google Reader Help.