Instead of "On Friday, 1 June 2009, 05:43 pm you wrote: ", would it be better that the name is displayed instead, if the dialogue was exported and archived and the people who are reading it would not know who the "you" is referring to - similar to forum where the user's name is always displayed regardless of who posted.

Also create a class for this text and increase the font size slightly as it is too small for some users.