There’s a great post here on some of the design features of the Ribbon in Office and how the Backstage View came into play over the last six years.
I am one of the early naysayers of the Ribbon, but also a convert. I’'ve grown to like the more standardized approach to grouping features of the applications and it has become quite intuitive.
Most people I’ve talked to who say they don’t like the Office Ribbon can provide very little reason why, other than it’s not the same. If you show them a couple of the features they are usually quick to re-evaluate their stance, and if they use it for a while they usually start to like it (at least enough to use it without complaining!).
I’m still working on one lady at my office…she’s a Mac user and a Ribbon hater! ;o)