With Excel, I'm not sure. But if customers who are getting increasingly greater exposure to UNIX, through various channels, learn about UNIX alternatives to Active Directory and Exchange that work as well or better, but which cost less, it may well come to pass.
> learn about UNIX alternatives to Active Directory and Exchange
Can you name one, good alternative to Active Directory and Exchange that runs on a Unix platform?
As someone that spent almost a year trying to find an answer to that question I can tell you that there isn't one. These are the areas where Microsoft is still above and beyond anything else out there.
Apple's 'Numbers' is actually quite good for most use cases, it's quite a bit more elegant as Excel anyway. The problem with Apple is their lack of experience in business support and their shortcomings in Q&A in the mac department lately. But windows 8 will definitely open up opportunities for contenders like Apple and Google in the business world.
Here's the key feature of Numbers vs. Excel: It not only has multiple Sheets, but multiple tables per sheet. Besides tables you can for example add text fields and images to a sheet. This makes it much much more natural to create reports and it encourages to split up your huge tables in logical units.
Oh and one other thing: Modifying columns/rows is consistant over all iWorks applications: Alt + arrow-keys let's you insert rows/columns above, below, to the right or left. MS Office's inconsistency and lack of hotkeys for such an essential feature makes me rage every time I use it.
Numbers sure has shortcomings though: no pivot tables, very limited scripting support, limited filtering / data manipulation. That's why I look at it as a very good spreadsheet tool, but not a data analysis tool - that's when Excel and/or Matlab come into play.
