The number in the brackets is a unique id for the character. Think of it as a numerical representation of #CHARID.
It is consistent between each time I login for my characters on a shard. I just tested it logging in and out for a made up conversation with myself.
![Wink ;)](http://www.scriptuo.com/Smileys/yarex2/wink.gif)
I also tested that each character on the account has a unique ID there.
So it really is just keeping the same name characters unique in the conversation. Nothing more complex than that.
So the content doesn't have a lot of purpose unless you are trying to isolate the difference between a real name and a modified name with an appended number.
So if I create my character named "The Ghost" along with my friend on the same server, one of us will invariably be named "The Ghost2" while the first one to login was named "The Ghost". Who gets the '2' addition? Not the more recently created character, but the more recently logged in character. If I have the '2' version and the other one logs out, I do not magically become "The Ghost" now... I remain "The Ghost2" until I logoff. (I am unwilling to test this to see what happens with 3 same named on the server...
![Wink ;)](http://www.scriptuo.com/Smileys/yarex2/wink.gif)
Personally, I am interested in the filtering of real conversations vs. junk. A tool like this would be really awesome if it could filter stupid advertiser phrases barking about their wares for sale for real $$... but that is just a wish list...
![Wink ;)](http://www.scriptuo.com/Smileys/yarex2/wink.gif)
I modified the attached picture for anonymity to all involved but it still gives a nice illustration to go with the explanation.
Gaderian