I have a love hate relationship with the ribbon - it is a radically new concept that works some of the time and other times is awful. That said it has potential. Why the big download - well MS office has been a dominent app in the work place but this may be because it offers a standard for employers.More than 2.5 million people downloaded Office 2010 beta. More than 2 out of every 3 people who responded to the survey by Microsoft last month said that the Ribbon makes it easier to discover new features. That's a phenomenal statistic that shows how many people recognise importance of usability and the role that GUI plays in learning and using a product's features.
Another thing that annoys me to almost ditching MS is the constant desire for feedback when you spend enless circular trips in the help and you get "was this information helpful?". Look at MS Office 2007 Word - and see if the help is obvious - the icon is there but from a GUI design seems to say only use this if you are absolutely insane!
Another memory triggered about marketing surveys - I was attempting to get marketing data on the UK Water industry and used a professional external marketing company - their first response to hearing the brief - "what answer do you want?"!