A new trend I’ve seen over the last few years has been the tendency for people to call each other to check and see if they read the email that they had sent. To me, it says a couple things about email:
1. Email is not the best way to communicate anything immediate or important.
2. If you have to call to ask someone if they read your email, you probably should have called in the first place.
Where it is possible, use a phone to make a call and get the answers you need, and only use email if that is the preferred method EXPLICITY expressed by the person you are communicating with.