It's probably largely down to the definition of what a smartphone was back then. The same graph scaled by market size or including dumbphones would be more interesting.
Yeah, I was confused by Windows' apparently-large share as well, and I figured it was a definition thing as well, but if you look at these sales figures:
Microsoft sold 14 million smartphones (or rather, their device partners, probably mostly HTC back then) in 2007, but according to this article from 2007, RIM was running at about 9.6 million devices a year, which matches what wikipedia says:
http://en.wikipedia.org/wiki/Smartphone#Historical_sales_fig...
Microsoft sold 14 million smartphones (or rather, their device partners, probably mostly HTC back then) in 2007, but according to this article from 2007, RIM was running at about 9.6 million devices a year, which matches what wikipedia says:
http://www.computing.co.uk/ctg/news/1830466/blackberry-sales...
So at some point in 2007 Microsoft some crazy how had something like a third of the smartphone market.