I've added three new functions to the ikiwiki VCS interface to support renaming and removing files using the web interface. The mercurial and tla rcs backends need implementions of these functions.
(The maintainers of these backends have been mailed. --Joey)
Also, currently git is the only VCS to have support for untrusted push. It may be possible to implement it for other DVCS, if they offer a hook that can be used to check incoming pushes early.