Nokia's intentions toward Maemo and how the new, open-source platform fits in with their existing S60 smartphone OS have kept the rumor-mongers going for months now. Only last week, SlashGear columnist Avi Greengart asked whether the Finns should junk S60 in favor of Maemo; according to this slide from Nokia's Capital Markets Day, the prognosis is actually worse for S40.
The graphic - which compares OS market share for Nokia's devices in 2009 and then 2011 - suggests that rather than ousting S60, Maemo will instead squeeze in at the expense of S40, the entry-level OS on Nokia's budget and mid-range devices. The indication seems to be that S60's reach - with a new UI, Nokia promise - will be extended down the line-up to contend with users expecting more from their handsets, while Maemo slots in at the flagship end of the spectrum. Indeed S60 device share actually increases from 2009 levels, rather than decreasing.
Of course, there are no actual figures so it's hard to tell exactly what Nokia expect to happen. The company has promised two "major device milestones" in 2010, but earlier rumors suggested that only one new Maemo device was planned for next year. If that's the case, 2011 will need to have quite a few more Maemo smartphones on offer if it's to grab its chunk of pie.