Office's dominance or otherwise isn't down to functionality, it's down to corporate habit, compatibility, user familiarity and a big ol' dose of FUD about using something different.
Until you find a way to deal with those for major corporate clients you could produce the best productivity suite in the whole world and you still wouldn't shift Office.
Look at the Office 2007 transition. They fundamentally changed the UI, broke alot of (poorly conceived and implemented) customer-implemented applications and changed the file format. They were in many respects new applications.
I worked for a very large organization that very strongly considered a major embrace of OpenOffice. The lawyers loved it, ODF scratched number of political itches, and Microsoft Office spend is incredible. User preference is weak when you're converting a $10,000,000 annual Office subcription spend into $500k of support staff expenses.
Problem was, when the time for talking ended and testing began, the application was universally reviled. The problem wasn't that users didn't like the apps, but they couldn't get things done.
Office 2007 was a pretty specific case where MS gave people an opportunity. The UI hasn't changed that much since Office for Windows arrived and it won't be repeated for at least a decade, probably more.
As an aside, the interesting thing is once people get their heads round the UI they pretty much universally like it, it's just the instant reaction that's so bad.
I did try OpenOffice for a month (pre-Office 20070 and you're right, it's horrible.
But even if it was functionally equivalent there are still reasons Office wins - because it's safe and because it's the defacto standard.
Even the cost isn't that big a deal for companies because they get security in exchange and that's one of the things big companies value above all else.
Office's dominance or otherwise isn't down to functionality, it's down to corporate habit, compatibility, user familiarity and a big ol' dose of FUD about using something different.
Until you find a way to deal with those for major corporate clients you could produce the best productivity suite in the whole world and you still wouldn't shift Office.