[zokier]

I think that's a double edged sword thing. OOo while similar, is still somewhat different than 'old' Offices. You might think you know it well because it feels similar, but the little differences makes your work inefficient, as you try to use it like old Office. On the other hand, new Offices forces you to relearn some things, and because of the visual dissimilarity you (hopefully) don't try to apply your old knowledge to it.

Note: I don't have anything to back this theory of mine up, so take it with a grain of salt.