Yes, it is amazing what they achieved with MS Office. Yet, there are plenty of companies who actually are trying an Office-free life as the licences are actually quite expensive. Compatibility between various Office programs (alternatives) has increased and for basic stuff Google Docs works actually nicely.
I found the relationship between MS Office and MS Windows the most interesting. How strong will MS Office be, without Windows. Office is the Killer app that Windows has. But a lot of people are steering away from Windows.
This is not going to happen overnight, but it might happen sooner or later.
Also - plenty of companies are still working with Office 2003 (or even 2000). The cost op upgrading is pretty significant, so companies wait longer and longer for that. That is very bad for innovation (as you keep being stuck with older software) but good for the companies wallets.
Editing of documents (albeit simple editing) is something people want on their iPads (and to some extend on other smaller devices too). Do not agree with you there.