The main purpose might not be to attract a wider userbase, but I think a bunch of the issues that plagued forum users throughout the years need to be fixed if Bitcointalk is to keep the ones they already have. Releasing a new forum that turns out to be inadequate (feature-wise) could have worse consequences than not creating a new one at all. It might become the reason why some users bid farewell to the community if they realize they waited all this time for something better, but it never arrived.