ok, for June 20, 2008: Do what
you need to do. If you need word editing capability now, you need eOffice. Or upgrade to OS 4.5 now. It is according to your need. eOffice now, or OS 4.5 now.
Summary: Only Vodafone.de has released OS 4.5 officially, and it is available for your device, with DocsToGo, and limited editing ability. If you don't want that version of the OS 4.5, and want to wait for a later version, no one can tell you definitively when, or what carrier will be next. There is rumor that June 24 is the target date for some. It appears BIS 2.5 will be implemented next Sunday evening. I would think OS 4.5 would be more widely available by then, but that is all a guessing game.
But DocsToGo is officially available now through the Vodafone.de release.
Good luck.