"F.L. Whiteley" wrote:
...
if you have an effective and powerful spam filter, neither matters, and once
_everyone_ has one, the spammers are dead. choose your ISP wisely
...

There is no difference for the spammers if you receive the spam and don't
read it or if some filter avoid that you even see it. As almost everyone
who has no filter is in the first case, why should it change anything if
they go in the second case? As long as the spammers would believe that there
is a 1/1000000 chance that their spam is read, they will try to send 1000000000000
spam (approximatively :-), this is the basic principle of spam. The only
correct solution is that their providers block the spam at its source,
but all this waste of bandwith is source of income for the providers,
so there is little chance that they will do anything to cut it. And we all
pay for it.