Short version - E-mail notifications of replies to your posts and private messages should be working again. Please check your spam folder if you have them enabled but aren't seeing the e-mails.
Geek Version: When we moved to a new server, we had to re-establish our mail credentials to verify that our e-mails were legitimate. Gmail and several others use protocols called SPF and DKIM to verify the e-mails are from who they claim to be from. I spent a couple of days getting that all set up, modifying DNS records etc, etc, and now gmail seems to be grudgingly letting our e-mails through again, but they tend to land in the spam folder. Go to Gmail.com, look under "Others" and then "Spam" to see if they're there. If you find them there, you can mark them as "not spam" and it should stop filing them as spam. Maybe. If it feels like it. Possibly.
Geek Version: When we moved to a new server, we had to re-establish our mail credentials to verify that our e-mails were legitimate. Gmail and several others use protocols called SPF and DKIM to verify the e-mails are from who they claim to be from. I spent a couple of days getting that all set up, modifying DNS records etc, etc, and now gmail seems to be grudgingly letting our e-mails through again, but they tend to land in the spam folder. Go to Gmail.com, look under "Others" and then "Spam" to see if they're there. If you find them there, you can mark them as "not spam" and it should stop filing them as spam. Maybe. If it feels like it. Possibly.