It is extremely rare for any backdoor attack to be performed by an attack on a specific IP. SubSeven, Back Orifice, and the like have to be installed on the target PC first. Normally this is in the form of a trojan horse, spread by bulk e-mail. You've got no way of guaranteeing that a recipient of a malicious attachment will run it, so you rely on sending out huge numbers of e-mails, and hoping that some people will run it. Even so, this is far more effective than directly attacking IP addresses one by one - because there is no patch for human stupidity.
When the system is infected, some of them phone home to the originator so that they are aware of a successful infection. Most hackers however would take the easy option and simply scan large blocks of IP addresses for vulnerable computers.
However, none of this relies on an IP address being disclosed. It is a trivial matter to find out someones IP. A list of IPs wouldn't spur anyone on.
Again, a list of e-mails is far more likely to become the target for spammers than hackers. Just knowing an e-mail address does not give you access to the e-mails.
Incidentally, before anyone freaks out about SubSeven or Back Orifice, even the most basic AV or antispyware software will catch these. Being behind NAT on most ADSL/Cable routers also stops them. Several of the big ISPs block the ports which they use. Both are like using a sledgehammer to crack a nut - big, slow, and not very effective.
And the use of the term hacker for someone who uses either of them... well, that would offend most hackers. It's at the low end of script kiddies TBH.