I just read at http://www.webwereld.nl/nieuws/17064.phtml (Dutch) that Sun and IBM no longer negotiate (huh? Did I mis something?) with each other about developing an opensource IDE together.
But anyway. I don’t find this very strange. There are huge differences between Eclipse and SunONE. And the new opensource IDE would probably be built based on one of then (my guess: Eclipse), so the other party wouldn’t really ‘feel at home’.