The news via Jazz Shaw at Hot Air, Did We Just Find Life On Venus? but let's let the scientists explain in their own words:
In this leaked video, astrobiologist Janusz Petkowski from MIT explains how they seem fairly convinced we’re on to something and they don’t have an explanation (yet) aside from life.
At some point, the planet may have been habitable, but it spiraled into an out-of-control greenhouse effect that changed it utterly. (We don’t know why that happened, but for now, I’ll just assume that the Venusian fracking program was insufficiently regulated by their global government.) Could some microbes have found a way to survive in the more pleasant conditions found in the upper atmosphere for all of this time? Perhaps.
But there is one other possible explanation to consider. Remember those Soviet probes I mentioned above? Couldn’t it be possible that some Earth microbes hitched a ride on one or more of them, peeled off as the probe entered the atmosphere, and basically seeded the clouds with a starter kit for life? In order to find out, I’m guessing that we’d have to have a probe capable of collecting and returning some samples and examine them. If they have the same DNA as the microbial beasties found on the Earth, we might have our answer. But if they are something almost entirely different, then the case could be made for a true Venusian Genesis, and wouldn’t that spur some interesting conversations? Of course, if you happen to believe in the panspermia hypothesis (as I do) then the galaxy is probably lousy with life and it all shares some common ancestor, modified through evolution to fit the environment where it lands.
My guess is that it will turn out to be an abiotic signiture somehow. Remember, we're still trying to puzzle out and explain the results of chemical experiments from the Viking mission on Mars.