pgdumpall

Hello,
        I suddenly am required to move databases from one server to
another.  I have read some things on pg_dumpall and feel fairly
confident that I can move it over with a minimum of sweat.  However,
given the importance of  the databases to our organization and my own
inexperience with pg_dumpall, I felt that if anyone had suggestions for
smoothing the transition, please let me know.  If there is anything I
should keep an eye on, or if it is not as easy as I think it will be
(not that it ever is anyway), or if I should keep away from certain
flags, please let me know.
            Thanks.
            Lalo