Amazon is expected to reveal the actual number of Kindle Fires it sold in the quarter when it posts its Q4 FY2011 results on Jan 31.

Meanwhile, according to The Register, Jordan Rohan, analyst at Stifel Nicolaus, puts the figure at 6m units.

He reckons the tablet will become the "third ecosystem" alongside Apple's iPad-iTunes combo and the less content-focused Android platform.

If stats from app analysis company Flurry are taken at face value, the Fire has already become the leading alternative to the iPad as far as app usage goes, having nudged past Samsung in the two months or so since the Amazon tablet began shipping on November 15, 2011.

Rohan previously forecast Kindle Fire sales at 5m units.