Gartner just issued their report as well:

http://www.gartner.com/it/page.jsp?id=1306513

They look at overall sales of all devices and smartphone sales by OS. Symbian had a 46.9% share.

Curiously, both Linux and Other dropped in 2009. I don't know which category they would put Maemo in (or who's selling Linux phones other than Nokia). If anyone has a Gartner subscription, it would be interesting to see if the full report breaks out Maemo and how well it is selling.