That's fine for bulletin boards, where all you have to do is scroll up to read the rest of the history. However, until very recently (i.e. GMail) viewing the hi

That's fine for bulletin boards, where all you have to do is scroll up to read the rest of the history. However, until very recently (i.e. GMail) viewing the history behind a particular e-mail message required you to go back through all your e-mail and find the previous messages in the thread. On a busy list, this could be quite a bit of trouble. Hence, having the entire history in the message itself could be quite useful.