How many more features can they possibly add to Word?
At what point could the next upgrade of office just become a reshuffle of all the existing features - because no-one actually knows all the features anyway? How big will the monster get just to keep pace with the .001 percent of people who use all the advanced features which save you one keystroke in ten?
I'm not a power office user, I've never been a power office user and frankly I don't want to be a power office user, I just want a nice editing environment.
Spellcheck for vi would be nice though. The real vi that is, and not one of the vast number of "improvements"