I keep getting the error message that I can’t make more than three posts in a topic because I’m a “New User”, even though I started playing in January 2007. Sure, I quit two months into Warlords because of the ridiculous decision to take flying mounts away even if you’re max level, but I came back to play Classic and now this?
What’s going on? Has Blizzard been hiring people away from Bethesda?
Seeing as how you joined the forum on October 2nd, that would make you a pretty new user. (To the forum)
This forum itself was updated relatively recently, so you are a new user here.
check out this post for information on the way the new forum works. Mainly, trust levels.
The new forums have a Rank system, it has nothing to do with the length of time you’ve played the game. In order to advance Rank you need to be active and contribute. 
It’s character by character, and based on Forum posting. I’ve been here since 2005, and I still can’t add images.