To CLOS or not to CLOS?

> On Sun, 2007-02-18 at 18:22 -0600, Paul F. Dietz wrote:
> Over the past couple years, I have really learned to appreciate CLOS...

    Paul Graham mentioned at one point that after years of LISP
programming he never *once* used CLOS to get the job done.  Perhaps
because LISP's pre-OO parts are so powerful you can do a lot already
without resorting to objects.  But obviously CLOS has it's fans as
well.  If you are a Common LISP user, what do you like or not like
about CLOS?  For example, is the generic function approach the best
way to do OO, or does it have some drawbacks compared to the common
object-dispatched system?