Measured Internet good v. "bad" traffic

["Raymond, Steven" <steven_raymond () eli net>]

Have received complaints from usage-based-billing Internet customers lately
about not wanting to pay for the nuisance traffic caused by worm-of-the-day.
I believe that in the case of a short-duration, targeted attack that can be
eventually be stopped, a billing credit is probably appropriate.  But what
about these current plagues that go on for weeks or forever- what is your
network's response?
Some simply want the traffic filtered in our routers- permanently.  That is
my least favorite option.  Others want to simply not be billed for "bad"
traffic.  My reaction is to suggest that metered billing is probably not for
you, then.  But I could of course sympathize if I were footing the bill.
What are other network operators doing about this issue, if it is an issue
for them at all?

Thanks