[jyl]

Kindle sold about 7-8MM units in 2010, most estimates are 15MM-ish in 2011, AMZN doesn't disclose hardware units but does disclose eBook sales that are zooming (running +300% from last year, selling more eBooks than print books). Kindle is now $114 and likely breaks the $100 point for holidays.

Nook Color reportedly sold 1MM units over the holidays and maybe 2MM so far this year. Some number of the Nooks are being rooted.

So, actually, you could argue Kindle is the most successful non-AAPL tablet with the Galaxy Tab tied with the Nook Color. The advantage of the ereaders is that they have a recurring revenue model (ebook sales) so they can be sold at cost.

Basically the 2011 tablet market currently looks something like AAPL at 50-60MM units, Kindle at 15MM, Nook maybe 4MM - and everyone else fighting over 5MM to 15MM depending on where you are on the pessimist-optimist scale.