GPL and Copyright Notification

[August Zajonc]

Note: If this has been covered before, I'd be happy for a pointer to the
proper list thread or FAQ.

Let's say I put together a photo album script in php, or (another) forum
package, or another slashdot look-alike.

At the bottom of everypage, I print out

Powered by MyCoolSoftware
Copyright 2001 MyCoolGroup

Now I license my software under the GPL.

Now someone takes this software, and installs it on their own server. They
change it around a bit. And then they remove my copyright notice from the
bottom of each page, for whatever reason. Is this a violation of the GPL,
which says copyright notices must be retained?

Let's say this same person decides they want to improve MyCoolSoftware, and
start calling it MyReallyCoolSoftware. And then they change the copyright
notice, that used to link to MyCoolGroup, to a new ReallyCoolGroup's
webpage? Is this a violation of the GPL?

Assume in all cases they make their changes available to everyone. Do they
have to if they just run the modified version on their own server and don't
"distribute".

A large group have folks have made it very clear that removing the copyright
in any form violates the GPL is "odious" and "criminal", and that one is
liable for damages if one does. Scary.

This runs contrary to my understanding of the GPL, and I'd appreciate some
clarification from folks who've a better understanding of the issues. I'd
argue that the web page itself is simply the output from the script, and no
restrictions are applied to the output by the GPL. Thoughts? I can think of
a slew of projects (especially ones which integrate open source scripts)
that will need to add a bunch of copyright and powered by notices if this is
the case. And I dread to think of what folks on alternative platforms (phone
screens) will have to put up with if you can't repurpose the output.

Thanks for the help,
August

Please CC me as I am posting from off-list.