Well first impressions are good! First thing that hits you is the new animated boot up screen.
Microsoft have been quite reserved in the changes made to the main Office programs unlike the change between 2003 and 2007! It does look and feel much more crisp than 2007 though.
However they have made some pretty big changes elsewhere for example Outlook which is the first major upgrade for a good few years!
In Word:
They have kept the Tabs which are now even more logical, they have added some neat, handy features for example the Screenshot clipper which beats print screening and editing manually any day!
I do not like the new 'Office Button'! click on it and instead of getting a traditional dropdown list you get this:
Completely takes your document away from you and it is a bit OTT for me.
Excel, Powerpoint, Access are pretty much the same as 2007 but with the the new horrid office button.
As with Outlook, they have decided to dramatically change Publisher this time round, haven't used it much yet but it looks very good with some good new features.
the New Outlook:
Very good, I'm glad they decided to finally do an overhaul I don't think i'll look back. The tabs just make things so much simpler and quicker.