A thread at WebmasterWorld named Yahoo fixes 1bu "bug", Google still MIA discusses how Yahoo! is much quicker to act on a particular, and popular case of content spam.
If you do a Google site command on site:1bu.com you will see that Google is swamped with 86,700 or so results that have the following sub-domain patter: www.lasvegasmercury.com.1bu.com, www.religioustolerance.org.1bu.com and so on.
The specific case is all over the Web, as you can see by a Google search on 1bu.com google.
But take a look at Yahoo!, all clean. Someone is working harder to prevent content spam. :)