How did you get into SharePoint?

An interesting quote from an Active Directory expert got me thinking about SharePoint. The AD expert said: "The reality is, the IT infrastructure is not going to go away. You're going to keep some things local. Though if I were an Exchange guy, I'd think about developing other skills."

I AM interested in what effect BPOS and hosted SharePoint might be having on your job as a SharePoint admin or dev, but what his words got me wondering about was, are there any Exchange folks out there who have already moved into the SharePoint arena, whether because of the writing-on-the-cloud or simply because?

And if you're not an ex-Exchange person, surely you're an ex-Something now that you're into SharePoint (unless you were born after, say, 1990 and are really precocious). How does your background affect how you learn and how you work in SharePoint?

If you're a current Exchange person, you're probably not reading this, so I probably don't have to apologize for helping to spread rumors of your field's imminent demise.