---- I'm not convinced that this is entirely true any longer. I was under the impression that much of today's UBE was being sent by Windows machines that have been compromised and are relaying mail at the control of others and less from improperly configured mail servers (hence your point about idiot ISP's that don't block port 25 properly I suppose). I don't have any statistics on this though.
According to my logs, this would be an accurate statement. I get hit by a lot of brute forcers trying *@domain and just tons of stupid spam drones.. Nearly all coming from dialup win boxes (according to p0f they are win boxes). Luckily cbl.abuseat.org and the other various rbl's do a pretty good job of keeping them under control. I very rarely see someone rejected as being an open relay.
However, the second someone has an open relay up.. it's a spammer heaven.
