So... camaro6.com is currently 'parked' at GoDaddy which means someone owns it. I am assuming that the owners of camaro5.com had the foresight to purchase that domain name since, ya know, they are trying to build an empire here.
Advertising pays!!! And having an active forum like this is a HUGE commodity.
When you go to camaro5.com, you get 5th gen news on the main page and there are a number of tabs to choose from, including the forums. When you click on the link to the forums, you get the root of forums - not just 5th gen stuff. You got not only the 5th gen stuff, but they allocate for anything that is required and reasonable to organize the masses, information and topics. Adding 6th gen is trivial.
The database for the forums cares not for the domain name. If you navigate from carmaro5.com or camaro6.com, it will be the same forums, your browser will just stick with the domain name you entered with.
For all intents and purposes, the camaro6.com domain will just be a new folder on the same web server holding camaro5.com. Nothing changes except for how they integrate 6th gen into the forums.