Agree entirely on the first paragraph. I want those, and think that the long-term benefits will outweigh the pain of moving.

Re: devs, it's not quite so cut and dried. Our devs are split between knowing cvsreport.pl -d (which has its own sets of problems) and Mercurial. On the other hand, the ones who actually use Mercurial are also more often the ones that are more active as devs.