No, my email is still the same as the one I registered with. I have not changed anything in my account/profile/settings.
The email-notification settings for the messenger are pretty straight forward: Get an email when "I receive a message". This option is on by default and can't be toggled. I'm certainly not receiving an email for every PM I get. At the moment it seems fairly random whether the system sends out a notification or not. CC is white-listed in my email, so it doesn't get sent to the junk-folder either.
Looking through the notification settings, I see also toggled on by default is "Someone quotes a comment or post I made". Thank god the system does not do that. I switched it off now, just to be sure.