Remember the Motorola Xoom tablet, Google’s first attempt to compete against Apple’s iPad? It was only a bad dream. Google Chairman Eric Schmidt is now promising a purely Android tablet “of the highest quality” in six months.

Schmidt’s comments to the Italian newspaper Corrier della Sea (Slash Gear has a report in English) follows the 2010 release of Motorola’s Xoom tablet.

What’s different this time? The new tablet is in the “Nexus” category of devices using pure Android. The Motorola Xoom used Honeycomb, a tablet-centric version of Android. The Nexus tablet Google is forecasting will use “Ice Cream Sandwich,” a version of the mobile software combining both Honeycomb and Gingerbread. The Gingerbread variant of Android is aimed at smartphones. Last month, the Galaxy Nexus smartphone was unveiled using Android “Ice Cream Sandwich.”

What’s behind the push for a Nexus tablet? Perhaps it is the success Amazon is experiencing with the Kindle Fire. The Amazon tablet is powered by a heavily modified version of Android which links to a number of services offered by the online retail giant. Google would likely prefer the first successful Android-based tablet be one that includes features tightly woven into the Mountain View, Calif. company’s family of products, such as Gmail and others.

The Nexus tablet will become a litmus test for how well Android can transfer from smartphones to tablets. There have been numerous flame-outs by Android tablets with HP’s defunct TouchPad likely the most spectacular. A key problem for iPad alternatives is that all tablets are measured against the Apple device. I’ll buy anything, as long as it operates and looks just like an iPad, is an often-heard response from consumers.