It is quite surprising for me to see how Excel rules the world of business. I know that many people in different companies, big or small use Excel for their daily jobs. But, until recently, I have understood how much impact Excel does have in the business world, and why it is the case.
These 2 excellent posts describe most of the use case of the Excel, why people still use it in the professional world, even in JP Morgan. I think Excel will rule even in the next few years, due to its ubiquitous usage, and many people support it (or its format): Microsoft (of course!), Google (with Google Docs).