Any hints of finding that patent? I ran some searches and didn’t come up with much.

Great question. You’ve raised the question of spammers who attempt to promote sites by manipulating other services. Where there’s an audience, they are bound to come. Wink does need to prevent bringing in spam from other sources, as do the search engines when they decide whether to index a site.
The model we are building is designed to classify spam even if it was tagged by several accounts, and filter it from our input. It’s typically become an arms race between clever tricks to manipulate results and algorithms to block the spam. With user input we add users’ voices in addition to the algorithms.
That said, we have seen that some sources are more susceptible to spam than others and if a source became overwhelmed with spam we may consider excluding that source. That’s the approach – sorry if I can’t go into too much detail about our specific algorithms. As you said, we too hope Wink gains traction before the black hats try to degrade the service.