There were many e-mails sent out regarding projects which were marked as inactive.
These e-mails, in the format of:
We're sorry, your project, <Project Name> (http://wow.curseforge.com/projects/project-1234/), has been marked as inactive on CurseForge/WowAce.
Recently the site upgraded its project status component and as a result all projects which have been previously merged or deleted were marked as inactive again, causing the e-mail to be sent out. Your main projects have not been affected in any such way.
-Note from Kaelten: Yea guys, we apologize for the mixup. We've already patched the cronjob so that such a thing won't happen again. Also for those of you who have many projects that were marked as inactive last night sorry for the span :)