If office 2007 was the first you had used... It would also be the last...
It's just
that good?

I started with Word 97 on a 486 portable running Windows 3.1.
Spent a long time with Office 2000, and finally onto 2003 (thanks for the reminder) for a few years.
97 - 2000 was a blissful expansion of functionality, but what little had originated from 97 remained basically the same in terms of menus and keyboard activation.
The changes from 2000 - 2003 were annoying (insert>picture (alt, i, p) became insert > object (alt, i, o ... wait for appelet to appear ... scroll down list of object types ... select 'image')).
2003 > 2007 was just a completely new UI, and might as well be a change of program entirely.
For comprehensive Word/Excel users (and I mean across a broad range of their massive functionality, not just knowing how to format fonts, bullet points and paragraphs or do a vlookup), such a change in UI is crippling, and can easily double the time taken to prepare a document to professional standards (even just using relatively basic functionality like references, indices, tables of figures/equations/contents and consistent styles).
God knows what the industry cost was for companies which blindly upgraded, just in lost productivity as people struggled to adjust to the new interface.
I didn't even bother trying Excel after trying to use Word. I'm just grateful MS issued the Office 2003 compatibility pack (docx, etc) which essentially extended the life of 2003 for another few years.