Not saying it is the ideal solution, but even as an interim solution until you find the right software, you could use a shared Google Calendar and setup pre sc

Not saying it is the ideal solution, but even as an interim solution until you find the right software, you could use a shared Google Calendar and setup pre scheduled reminders for you and your team. That way 2 days ahead each month for each client (or whatever) you get your reminder. Outside of that, you could try Basecamp to manage your projects and use the To-Do list as a reminder system to send your team the reminder to do the blog post etc, and then they can mark the task complete in Basecamp once it is done. Just some ideas as I am not sure of any specific software built for your need.