The one feature I miss from Mercurial is the "hg serve" ability. When combined with the zeroconf extension, it made it really easy to push/pull changes to/from other developers. Since switching to git, I don't think we've had one (vcs) push that included commits from multiple developers, but we used to do that all the time. I know git can coerced into doing something similar, but hg made it so damn easy that developers actually used it.
Addressing your actual point, most shops won't use the full value of a dvcs, but they'll all get some benefit of it being a dvcs because each and every developer's machine has a backup of the central repo which, in the event the main git server dies, can be used to restore everything to it's previously happy state. When you use a vcs like svn, you need to be a lot more paranoid about backing up the central server or you risk losing revision history.
