Tasks are a better way to do this.

This would be very interesting if merged with the Virtual Attendant functionality in 5.4+. You'd be able to link an object to an attendant (using context links), which would allow it to oversee messages (SLA enforcement, etc)

No idea about the new Virtual Attendant functionality noted, but just wanted to mention that this is something we've often had various use cases for. To a large extent we get around it just by setting tickets as 'waiting for reply' and reopen on the desired time, but it doesn't always suit.

Sometimes we need to leave ourselves a note to do something at some future time, and have a reminder to do it at that point. (obviously all relating to a ticket). Yes tasks probably fit that need better, but if the tools are already there do handle that (or even will be in 5.4 / 5.5) we probably need a little more by way of guidance to show us the possibilities :)

See:
http://cerberusweb.com/support/kb/article/64-Scheduling_reminders_about_anything_using_Virtual_Attendants