That probably won’t be very useful for fraud detection in California wine—the levels of cesium-137 are barely detectable, and even then, only if the wine is destroyed.
But the result does show how nuclear disasters can have unexpected consequences long after the fact.
The title is the meat of this article. Also, the first half of the article contradicts the last sentence. This was completely expected based on previous data. If anything the Fukushima radiation is less pronounced than you may expect from that previous experimental evidence.