Malatesta, who's also a superstar in our own forums, has a post up over that PPC Geeks detailing how to get the WM6 version of office on WM5. In other words, those of you who aren't lucky enough to have an upgrade on the way may still be able to get your edit on. Docs To Go is still probably a better option for you (or at least a less legally-murky option), however. In any case, WM6 and WM5 are so similar that this isn't likely the last time we'll see WM6 "exclusive stuff" show up on WM5 devices.
Mobile Office from WM6 has been successfully, ahem, ported to WM5 devices and works wonderfully.