Still I wonder what Sun thought they were going to do with this... I find it fascinating they’d pursue a heavyweight UX project such as a window manager with no clear stake in the game... a last chance at pushing for Solaris adoption?!
Not sure. But around that time Sun had invested heavily in the Gnome project and made a lot of commits that enabled lots of more "boring" things to be added. eg. i18n, accessibility etc. This was because with Linux based Java Desktop (i.e. their polished gnome implementation) they had won various corporate & government contracts in different industries which required these changes, benefiting the gnome project immensely.
Whether the very popular compositing WMs (e.g. Metacity/Compiz) indicated a necessary investment in that area (hacker prelude to new industry), I don't know.