Simple example:
-----
From: Bob
Yes.
Alice wrote:
> Wasn't that new Looney Labs game
> great?
>
> Oh, BTW, there's this new sushi
> place. Shall we check it out?
AND Maybe Bob could have said "Yes, the new game is great."- and Top Posting would have worked. I think maybe we should demand full, complete sentences, too. I always figure if I can't tell exactly what said, it's either not a big deal or I can ask for clarification.