I think a lot of the discussion in the forums was due to the remodel of DCA and the events leading up to it. The Micechatters discussed every square inch of what was being done to the parks multiple times over. Now that the DCA remodel is complete there really isn't much to talk about. Sure, there have been a few minor things since then like the new PFF and Starbucks coming to Main Street, but other than that nothing much has been added to the DLR that requires such scrutiny as the DCS remodel did, and all the other peripheral projects during that time as well.
My prediction is that MiceChat will be relatively slow for awhile until a new project comes up and then there will be a flurry of discussion, only to die down again until the next project surfaces.