I think editting of Office documents is also a Maemo OS thing, not a hardware issue. And I thought it was confirmed that the n900 will be getting the Maemo 6 OS anyway?

Mid 2010 should be interesting (when I'm planning on getting the n900). If the successor is out I might consider it. Though I would take a hardware keyboard over a better camera and even a capictative touchscreen if the n920 was keyboardless.