Google released its first branded tablet in June, but there’s been little said about how it’s actually doing in the market.

But in a recent interview with The Wall Street Journal, the chief financial officer at Asus — the company that makes Google’s tablet — gave the first hints of how sales may be going.

“At the beginning, it was, for instance, 500K units a month, then maybe 600, 700K. This latest month, it was close to 1 million,” CFO David Chang told the Journal.

That’s higher than many analysts were predicting based on Google’s revenue, which seemed to indicate that the tablet sold around 1 million units since its summer debut. While significantly less than 14 million in sales Apple reported for the past quarter, the sales figures show the Nexus 7 has made strong headway in the growing tablet market.

If Nexus 7 numbers are on the rise, it may bode well for the next two tablet models in the line — a revamped version of the June tablet and a larger, 10-inch version meant to compete with Apple’s iPad. Google announced those two tablets Monday in a blog post published in lieu of a New York event canceled due to Hurricane Sandy.

The announcement means that Google and Apple are now fighting a two-pronged tablet bout — heavyweight and featherweight — with the introduction of the Nexus 10 and the iPad mini.

Competition will be particularly fierce in the smaller tablet market, between those two companies and Amazon, which posted an unfavorable comparison between its small Kindle Fire and the iPad mini on its homepage Monday.

Unfortunately for Apple, it has almost nowhere to go but down. The company currently commands the majority of the worldwide tablet market — with a bullet — but may see iPad sales erode under the pressure of lower-priced competitors.

One of Apple’s biggest competitors may even be itself. According to a report from Computerworld, at least one analyst thinks the iPad mini will steal up to 50 percent of its sales from the iPad. Other analysts have put that figure closer to 10 or 20 percent, but Tech-Thought’s Sameer Singh looked at data on the iPad 2 and the third-generation iPad to get a hint about cannibalization.

Singh said documents from the patent case between Apple and Samsung showed that the “iPad 2 cannibalized approximately 60% of 3rd generation iPad sales, i.e. for every 5 million iPad 2 buyers, Apple lost 3 million 3rd generation.” He expects that Apple will see a comparable rate with the iPad mini, which in turn could drive its profits down.

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