This isn't reverse-engineering at all. Frankly, I think this is a reasonably cool project, but it's brazenly dishonest of the author to claim he "reverse-engineered a company" when all he did was conduct elementary statistics on an open dataset. You can reasonably expect that there's much more to OPower's data analytics suite, and furthermore, a company is of course much more than its flagship product.

There are lots of smart metering companies: why is OPower among the most successful? Maybe the interesting thing to really think about is not their analytics but their sales and marketing strategies.