"What about a "mark as spam" button?" - NO!! Yahoo had them ones and where they are now?
Exalead's result pages are full of Spam, for example: http://www.exalead.com/search?action=search&q=lista+s...
I suggest a solution: use an automatic bayesian spam-filter based on users' input. You should build a community like dmoz.org with an "anti-spam" proupose, a sort of Spam Cops Squad.
Humans do it better, and they can do it in their mother tongue, because exalead is european, and the spam is not only in english.
sorry for my poor english,
bye.
What about a "mark as spam" button?
As Exalead already uses dmoz.org it doesn't make sense to start building a new anti-spam community; but a simple and easy-to-use button will work fine; a program could just take out pages which are marked as spam by at least a quarter of users who see them.
A "rate up", "rate down" button would also be very useful. The results are quiet fine but there's always something to do better. (such buttons would get near to what wikisaria is going to try)
anonymous