Maybe a hot gallery and someone shared the URL with friends or any number of reasons. I don't think just 200 some uniques makes the numbers statistically significant. Was this a single banner, text link, gallery with links or what?
Did you change anything?
I notice for example the ratio of raws to uniques can grow depending on the link. Take
DatingGold for example. If you use their link that lands on a page of multiple date opportunities, the chances are high the surfer is gonna check out more than one. That drives up the number of raws compared to uniques and our hope is that something will catch the surfer's eye and lead to a conversion.