K2 Notify Admin plugin will let you set up :
Global email alerts to nominated emails when a K2 front end item is submitted
Specific email alerts for nominated emails when content is submitted to specific K2 categories
Send email notifications to single or multiple email addresses
- Includes comment notifcation (when using K2 comment system)
It adds a configuration screen to K2 categories [admin view] which enables you to specify who should receive an email when a submmission is made on a per K2 category basis. You can also override these settings in the main notify plugin to set site wide global options.
[It is not a global content subscription solution]