"is distributed version control so much better than centralized version control that we will all eventually be using a DVCS?"
I can't predict the future, but I do think DVCS is fundamentally superior. Joel Spolsky called it "possibly the biggest advance in software development technology in the ten years I’ve been writing articles here." (http://www.joelonsoftware.com/items/2010/03/17.html)
Let me describe a key weakness of centralized version control and how decentralizing fixes it.
Say you're working on a project with others. All of you commit to the repo, and you use it to deploy to production.
When you're coding experimentally, you have to make a choice: do I commit often, possibly giving half-baked code to my peers? Or do I commit only when I'm totally done, with long periods between commits, during which I can't roll back changes?
DVCS eliminates this painful choice. Commit as often as you like on your local repo. When your code is ready, push up to the shared repo. If you like, you can even do better: push up to a shared development branch for review and merging into the deployable branch. And better than that: if it took you 20 false steps to get to the end result, doing stuff, undoing it, redoing it differently, etc, you can clean up that commit history to a single, logical, readable commit for your teammates to read.
That is fundamentally better for teammwork. Add all the stuff about offline access, etc, and it's just clearly better.