Stumble Upon is similar to Digg, in that users can give you either a thumbs up or a thumbs down rating.
Zimbabwe was given a big thumbs down by the miners.
Users may have compared it to other similar scents, or they may have similar tastes to those of the recipient and give the perfume in question the thumbs-up or thumbs-down.
Natalie Portman's skinhead look from a few years back also gets the thumbs down from those who don't have Natalie's bone structure.
The network search page itself is also given the thumbs down by users and reviewers who think that the plethora of ads integrated into the page design is off putting and confusing.