If you'd quit a job because of the mail client on your desktop, that's your right. A colleague of mine recently gave notice because she didn't like the coffee in the cafeteria, and that was her right too.

Like it or not, Outlook and Exchange are still the best-in-class solution for enterprise messaging, which is why they're used. If you can't understand why that is, then I hope you've never worked in an enterprise. Perhaps you'd prefer Lotus Notes?

I'm not a Microsoft fanboy by any means; I have a Mac and use Gmail every day. But being able to put aside one's biases and pick the right tool for the job is the difference between an IT professional and a zealot.