I agree with madworm on this one. I have been cleaning up much of the spam along with others, and it gets tiresome dealing with the same things over and over. The success of the wiki will depend on Seeedstudio taking appropriate action to help prevent repeated attacks by the same individuals. If this means increasing security, so be it.
Certainly, this is a public wiki, and as such will be open to these sorts of attacks, but to do nothing other than deleting when it occurs will be an approach that will not work in the long run. Especially if it is occurring at the hands of what looks to be just a few individuals.
I think the wiki will find it difficult to get support from the desired community, if it is constantly ridden with spam. I know that I would find it difficult to continue contributing projects if no attempt is made to help the situation.
Mike