The thing is, the length of the thread and the title of the thread are often misconstrued. The thread is no longer about what its title suggests, it's about all things to do with the Boxster Spyder. If you start a new thread you'll still have people posting at the same rate on a new thread, such is the popularity of the model. The length of the thread isn't really relevant or doing any harm (though it is a nice indicator of how popular the model is, by the length of conversation about it). The value is that everyone knows where to post their Spyder query and have the attention of every enthusiast to help answer their query, because they're all committed to it. It's not about whether you can sift through 700 pages or not. Some will be subscribed to the thread, such is the community built up with it. Starting new posts for every Spyder topic would lose the ability to subscribe to the Spyder community as you couldn't subscribe to multiple new threads that you don't yet know exist.
What we do need to do though is to try to reduce the amount of catty confrontation which sometimes arises as that is what will have us perceived as chat room.