There seems to be some problem with the way the forum tells if a topic has had anything posted since your last login.
As an example, check out this screen cap:
http://www-personal.monash.edu.au/~sjwhite/wrox.gif
It shows that the last person to post to the topic was me, but that it's still a new topic.
It gets a little annoying at times, having to check every single thread because the icon can't be trusted
There are 10 kinds of people in the world - those who understand binary - and those with friends