Here's a graphical look: http://blog.datarank.com/recent-twitter-spam-behavior-quantified http://blog.datarank.com/recent-twitter-spam-behavior-quanti... Appea

Here's a graphical look: http://blog.datarank.com/recent-twitter-spam-behavior-quantified http://blog.datarank.com/recent-twitter-spam-behavior-quanti... Appears to have started on March 31st and has affected > 100K Tweets. It also appears to run between the hours of 2PM and 10PM PST, peaking at 7PM each day.