It's definitely better than before (for instance, it uses the print layout rather than the web one), but I think the icons and toolbars looked better in the 2010 style. Also, why does it still have one long page, Wordpad style, rather than separate ones, like desktop Word?
Word and Excel haven't changed too much (they were already good enough), but Powerpoint is exponentially better - it was a piece of *** before, and now it's getting close to being as good as the desktop version. Onenote also improved quite a bit.