I received a confirmation (from a party who I assume likes to remain
anonymous) that the T3 showers still existed, when he used them in
September 2003. He described them as adequate.

He also said:

There's plenty of room to keep your dry things dry. You enter a
slightly
enlarged public toilet and lock the door behind you.

The only real problem I faced using the facility was the total and
utter
lack of anyone to rent me a towel (the advertised rate was 1.5
pounds), and
the total and utter lack of anyone else in the airport to care about
such.
I ended up purchasing a small bar towel for 5 pounds at one of the
souvenier shops which proved to be just barely adequate. Now, I do
not
travel without it! Be sure to bring some flip-flops to wear in the
shower.

I guess that I'll be packing my own towel! I'll take an old one, so I
don't have to carry a wet one around.

Does anyone have any information on the showers in T1? [I'm now less
than 12 hours from leaving for the airport!]