In trying to understand some quirky things about the forum in regards to people not seeing posts I made some modifications to try and help track it also it helps in showing you new posts since your last visit. The key being last visit, meaning when you last logged out and returned. Apparently some key functionality of seeing all new posts and topics comes from actually logging out.
That and if you are experiencing issues logging in or seeing any new posts, this may be a result of one of two things, one being the header being used for banner ads and second is if your using a work computer and your username is is different it may not like the way your computer creates cookies.
Forums are an everlasting task, I backup the forum at least once a week, run maintenance scripts and check for errors, many of these tasks are as simple as clicking a button, and I am always looking at ways too improve things. If you have any suggestions please fire them at me and I will do what I can, if you dont like the green let me know what works best for you.