> I'm finding some records that exist in the master that do not exist in
> the slave.  I'm also finding records that exist in the slave, that don't
> exist in the master.
>
> I simply don't understand how this is possible.
>
> I'm assuming the first issue is a record that was never populated to the
> slave, whereas the second would be a delete that was never populated to
> the slave.
>
> Further, these examples are 4 days old, so it's not the case that the
> slave just hasn't caught up.

The more you describe this, the more this is sounding like a case where
the databases may have (somehow?) gotten corrupted.

It is not self-evident whether it is the origin or subscribers or both
that have gotten corrupted.

If that is the case, then it is not evident that there is any problem with
Slony-I in this.  This isn't something Slony-I should have caused, and,
alas, it is not something it can necessarily protect you from.  Notably,
if both DBs have been corrupted, all bets are off altogether.

I think you need to look into your backups :-(.