I swear that I saw someone mention this already, but I can't find the feature request.
Game Hub authors should be able to disable the forums on the hub completely. For developers like me who maintain an off-site community, it's important to be able to direct all discussion (including support questions) to the appropriate venue. The existence of another forum is both confusing for users and a hassle for the developers to have to worry about.
Also, the loss of the external forum link from the hub has caused some confusion: apparently a fair number of players took advantage of that link.