Email - appropriate usage

What are the appropriate and inappropriate uses of email? A friend's divorced dad told her about his remarriage over email. Didn't sit well with my friend. Is this the currently accepted way to break up with a paramour?

In a refereed journal article from EDUCAUSE, faculty note they like using email for communication, but don't like answering substantive questions thru email (lecture clarification, grade discussion, etc), BUT students still feel more comfortable asking these questions through email (perhaps due to shyness, or because written questions can be better composed).

If it's a personal issue or grades - office hours are the most effective and appropriate way to communicate, but if the whole class could benefit from a response– instructors are increasingly blogging it. They can share the info once, and archive it indefinitely to pre-emptively address future class needs - without necessarily identifying the source of a question.

It's interesting what the article mentions in their conclusion:

Additionally, we propose that the development, communication, and adherence to agreed-upon e-mail expectations, norms, and guidelines would improve communications, lessen faculty and student frustrations, and alleviate student anxiety.

Achieving these goals requires instruction in e-mail use, however. Despite objections to attending e-mail training, both faculty and students agree that it would be beneficial—for each other. By raising awareness of the association between student success and one-on-one communication with faculty in an environment where e-mail serves as one of the primary methods of contact, we hope that both faculty and students will begin to see the value of e-mail training and become more willing to attend.

Whatdda ya think?