Something to keep in the back of your mind.

A blog post by Ellen Carney at Forrester (H/T to the Wall Street Journal for coverage) covers efforts to roll-out Google's insurance comparison site/portal, Google Compare, in the U.S.

"Soon, Google could be piloting its Google Compare auto insurance comparison shopping site in the US, following the lead of its 2012 Google Compare UK site roll out," Carney writes, while also speculating Google may acquire, or work with in some other fashion, existing comparison site CoverHound.

Rolfe Winkler in The Wall Street Journal notes that in the U.K., Google also offers mortgage quotes and even credit cards.

Winkler suggests Google wants to offer similar services in the U.S., "potentially displacing existing middlemen."

Winkler notes Google already offers flight and hotel booking tools, though its flight search hasn't made a dent in the online booking space, which according to an October 2014 Washington Post article, remains dominated by Expedia, Orbitz, Priceline (and its Kayak.com), and Travelocity, which collectively have 95% market share.

Still, Winkler observes that, "The mobile revolution is putting more pressure on Google to build up 'vertical' search engines for specific categories, since smartphone users are being trained, for instance, to go direct to Amazon's app to buy products, or Expedia's app to book a flight or a hotel room. If Google doesn't provide more efficient services that cater to particular types of searches, it risks being cut out itself."

That leaves us to wonder. With insurance (soon to be) and travel out of the way, what is next for Google in terms of comparison services.

Might one day Google's strategy lead it to expand into retail energy brokering (assuming it doesn't want to take the plunge into a being an LSE)?

Would retail energy brokering be a natural fit to any smart home/connected home and big data service offerings Google is eager to launch (recall Google now owns Nest, which is being described as the "hub" (by Fool.com) and "central command" (by Bloomberg) of Google's smart home).