Confused repository.

[Rob Landley]

I accidentally commited a change on top of another change I thought I'd
rolled back, and since rollback won't go more than one back that means
my working repository is toast, so I replaced the .hg subdirectory with
the one from the website (copying the hgrc file out of it first) and now
the repository thinks the "current" version is an old commit from July,
even though the .hg directory I cloned from has the newer commits up to
yesterday.

Where is it getting this information from?

$ strace hg identify 2>&1 | grep '^open(' | wc -l
    621

Is there any way to do a checkout without changing files in the current
directory?

Rob