I'm an engineer and my company is very strongly tied with MS. Our intranet is really just MS Sharepoint with our logo placed on top. In fact, I might as well add Infopath to my list of apps if you want to be comprehensive. i don't really think highly of our IT group.
My wife is a business consultant. All she needs is Excel for "data", Word to type up reports, and Powerpoint to make pretty slides to help promote synergy, strategy, and *INSERT BUZZ WORD HERE*. Her company's IT is locked down hard and they can't use non-MS apps. I think they prohibit their work laptops from working with USB drives.
I figure start-ups have a lot more flexibility.