Information Week has a useful…
Road Map For Smartphone Operating Systems
…on their website. Anyone interested in trying to get a quick grasp of where the major mobile device OSes will be in the near future would find the table on their web site interesting. The table provides an overview of the near-future guess-timates for Symbian, Linux, Garnet OS (formerly Palm OS), Windows Mobile, Blackberry, and Mac OS X (Apple iPhone).