No, it's not. But, it may have triggered an automated detection algorithm at Twitter, affecting all users.
I don't have a Twitter account: is there an "abuse" button to report automated spam? If so, you may be seeing the effect of a concerted effort by the left to suppress it by reporting Wikileaks email URLs as abuse.
Yes, it could be human intervention by someone at Twitter. But, it could also be a group of people gaming the system by taking advantage of the lack of human oversight.
No big deal for a computer to handle, as I said.
I may have just a wee bit of experience in the field. :)