I would suggest that they would not be RBLed as
1] this is a list that can be easily (I assume) opted out of.
no. there is no way to opt out of it.
2] They are sending to folks that use the service.
yes. which is: everybody who has a domain in COM, NET, or ORG.
3] I see no effort below from the RBL team to try to correct their issues before action to put them on the RBL.
as a result of this nanog thread, folks from netsol are finally appearing willing to talk to us. we're waiting on a call back from their sales dept since it's their policy.
I would suggest that the RBL team suggest that there be a "kinder" way of folks opting into this "list" although I have seen much worse from "legit" mailing lists programs (majordomo) and maintainers (egroups).
now that they're talking to us, we're doing that.
A "kinder" way that could be suggested would be to annouce the list as an opt-in in some missive that NSI normally sends out such as domain payment requests.
as long as there is an existing customer relationship (i.e., money has changed hands -- not just "you surfed our web site, now here's your spam") i have no objection to an opt-in initial probe, and while i object lightly to an opt-out initial probe i won't blackhole somebody over it. but there's no way to make this stuff stop, and that's just unacceptable in light of the fact that we are ALL forced by current circumstances to be netsol "customers".