Well yep TDU 2 is kind of a failure, due to Atari and Eden not taking care of the costumers and listening to our opinion, as they said they would.
Normally, sudden changes, or rebrands and those kinds of things, lead to big fails, and loss of interest. I've witness that on other forum boards.
I think that if the change happens, and it should, it should not be too drastic, like a complete subject change. I think the game boards should continue, not only for TDU, but for tons of other games, which either have potential player interest, or modding interest. I am voicing my opinion with this post, i think that the forums should stay keen and loyal into racing/car subjects, including gaming; that does not mean that it can not cover other topics appart from cars/motorsports/driving games, but thats the original forum topic, and as i said, sudden changes and rebranding sometimes are not very healthy for a community. Something neat would be a subforum covering Future Releases, of any genre, for example, the new "Microsoft Flight".
If rebranding and changing is a strong idea, you should keep in mind what brought so many members over here, which was a racing game which is moddable, so members want to see more of that. I think a good measure could be, if rebranding does happen, cover racing games which support mods, and invite modders to post their mods here, to give those games a jump start over here.
Something definitely worthwile keeping is the spirit, all the TDUcK Pets, the randomness and irony and sarcasm, that way it feels more of a house re decoration instead of moving out into another house.
Its just my 2 cents on this matter, sorry for the long text :p