Any Android connoisseur will tell you than when it comes to devices sporting Google's (Nasdaq: GOOG) mobile operating system, any gadget with "Nexus" in its name is as pure as it gets.

Google's Nexus branded line of devices are flagship devices that have always set the standard of what an Android device should be, coming stocked with Android versions as free from third-party modifications as you can get. It started with its HTC-built Nexus One, which was followed by the Samsung-built Nexus S, and most recently the also Samsung-built Galaxy Nexus.

Android tablets such asMotorola Mobility's (NYSE: MMI) Xoom have been lackluster, particularly when compared with Apple's (Nasdaq: AAPL) iPad. Xoom shipments were starting to go in the right direction but have promptly fallen off a cliff. Over the past three quarters, the company shipped roughly 250,000 units, then 440,000 units, and then down to 100,000 units last quarter -- notably less than even train wreck Research In Motion's (Nasdaq: RIMM) PlayBook shipments.

Xoom currently runs Android Honeycomb, which was a rushed mishmash tablet OS. Android head of user experience Matias Duarte called it an "emergency landing," with corners being cut just to "get tablet support out there." Android 4.0 Ice Cream Sandwich refines the OS for tablets, while also unifying it with smartphones.

Fellow Fool Tim Beyers long ago said Google needs a Nexus tablet to set the stage for a frontal assault on the iPad. Rumors surfaced earlier this year that Google was partnering with LG to launch a Nexus tablet over the summer, but that seed failed to bear fruit. The latest round of Nexus tablet talk is coming from a pretty reputable source: Google Chairman Eric Schmidt.

In an interview with an Italian newspaper, Schmidt said, "in the next six months we plan to market a tablet of the highest quality," amid the "brutal competition between Apple and Google Android." While this could easily be interpreted as working with its standard slew of OEM partners, it also implies the distinct possibility of a flagship Nexus-branded Android tablet.

Schmidt also essentially confirmed the rumors of its "Siri killer," Majel. He said Google has "the best voice-translation software," and the company is working on developing its technology to "do things similar to Siri."

With Android leading in smartphone OS market share, it's always been somewhat incongruous that Android tablets have failed to take off.'s (Nasdaq: AMZN) Kindle Fire seems to be roaring ahead, but its Android tablet brethren are less than impressive. Even Hewlett-Packard's (NYSE: HPQ) zombie TouchPad was grabbing more sales throughout the year thanks to its $99 fire-sale price.

My colleague Tim is right: Google needs a Nexus tablet. One that will set the standards for Android tablets with the Nexus brand and jump-start the Android competition to the iPad.

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This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.