Nothing raises the temperature among email aficionados like the debate over top-posting and bottom-posting in replies.
I have my own barbaric views 
on this topic.
QuoteFix is a plugin for mail.app that answers every bottom-poster’s heart-felt cry.
When installed, it places the cursor below the original message, or below the selection if you highlighted some part of the message before hitting the reply button.
And it does it well:
It also claims to remove the signature from the original message and to remove unnecessary empty lines from the original message.
I have found performance more patchy on these two fronts, but the plugin is still in active beta development, so it’s unreasonable to expect too much.
If bottom posting is your thing and you use mail.app, you will want to test it for yourself.
Get the QuoteFix plugin and read the installation instructions on its Google Code page.
Few things get the juices flowing faster than the top- vs. bottom-posting debate. 
David Heinemeier at Signal vs. Noise 
I generally prefer bottom posting, and mention that fact in my ebooks about Mail. But then, I also recommend selective quoting, not simply including the entire content of an email in a reply. The two practices make sense if done together, and less sense if you do only one. I wouldn?¢‚Ǩ‚Ñ¢t put a reply beneath several quoted paragraphs, because that?¢‚Ǩ‚Ñ¢s hard to read and annoying. But I would pull out a relevant sentence or two, to remind the recipient exactly what it is I?¢‚Ǩ‚Ñ¢m commenting on.
address them one at a time, bottom posting is the only way to go, because it gives the recipient context for each remark.
