hg update --clean -r tip resolved the problem…
[mpenning@host1 login]$ hg update --clean -r tip
resolving manifests
getting Protocol.py
getting Session.py
getting mp_getconf.py
getting mp_runcmd.py
4 files updated, 0 files merged, 0 files removed, 0 files unresolved
[mpenning@host1 login]$ hg up
resolving manifests
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
[mpenning@host1 login]$