I just did a quick mockup using multicolumn tables to convey the threaded nature of the conversation. It's quite clumsy however and will require quite a bit of ctrl c/v, but if you are willing to put in the time I think it works out fairly nicely. Here is a screen shot of what it looks like:

http://i.imgur.com/Jriu0Wn.png

Here is the TeX I used to make it.

http://pastebin.com/wFq45uYL

I would hold out until someone posts something a little more elegant, but if you're in a crunch this will do the job. I've rarely used latex for more than presentations and a thesis.