Is this supported in other scm systems? I know svn is a bit weird for not having an actual move command, but I've gotten the impression from documentation that this is supported in other scm systems?

I currently use the addchanges command almost exclusively, so that would be my highest rated command personally.

For me at least, I'd like to see it treated just like svn. Granted, I only use git as a front-end to a svn server, so there may be more complicated uses of git that don't fit this workflow. But that's the big thing for me - being able to point at a git repository and use it with the gui and such.