imalive1459 said:
According to UrbanDictionary.com:
http://www.urbandictionary.com/define.php?term=nm(LANGUAGE)
Quite Possibly the most useless internet/chat abbreviation known to man. 'nm' can be short for one of two things, 'Never mind' and 'Nothing much'.
Commonly misinterpreted by users, the abbreviation can be harmful, even fatal.
In this case, Tim is right.
It means No Message.
You would have to have visited and posted on a forum like the one most of these guys are from to understand that.
It's set up a lot like TI is...where a lot of the time a response to a thread is in the subject box instead of the message body box like this one.