The OCS team posted a PowerShell commandlet today that lets you pull out conversations between users and output to an HTML file. I'll try it out soon, but it has to be much better than the current method of writing your own SQL queries and retrieving some ugly looking code. Here's the link: http://communicationsserverteam.com/archive/2008/01/14/69.aspx
Update: I stood up an Archiving and CDR this afternoon and gave this commandlet a shot. Much better than digging through SQL logs and trying to parse out an actual conversation. Here's a screenshot of the resulting HTML page:
I'll probably tweak the script myself (left-justified text) a bit, but it's a solid improvement over what we had before.