I'm translating below the answer from my friend, Luca Mascaro (1):
Up to the beta versions of Vista and Office 2007, it doesn't seem to me that [a traditional view] is or will be possible, as far as the functioning and position of the icon commands is concerned. In effect, Office 2007 introduces a new paradigm, which is more usable and simpler than, but clearly different from, the former.
And as to the orientation problems this might cause, he writes (my translation again):
Yes, the problem exists, but Microsoft's reasoning is not wrong: in the end, a user-centered projecting approach means selecting a panel of users and work with them (in Microsoft's case, this panel is very wide). If this makes a program simpler for 70% of the users, then of course they [Microsoft] are ready to sacrifice the small percentage of users who find it hard to readapt.
(1) Luca Mascaro is member of IWA International WebMasters Association and was part of the team who prepared and wrote the Italian accessibility law (English translation of the law in http://www.pubbliaccesso.gov.it/normative/law_20040109_n4.htm )