Have you come to Microsoft Excel 2010 by way of Excel 2007, or did you skip directly from Excel 2003 or an earlier version? Those in the former group are likely to have a very different upgrade experience from those in the latter group.
If you're in the former group, you'll find a few small interface tweaks and a handful of useful new features in Excel 2010. If you're in the latter group, you'll find an overhauled interface that radically changes how you interact with common features and functions.
Either way, we've got you covered. This cheat sheet shows newcomers to the interface how to get around; it also explores features that are brand-new in Excel 2010. We've noted which sections of the story former Excel 2007 users can skip over.