If anyone want's to follow a match between two undefeated Twixt players, it's game 40029 between David J Bush and mirror_man. I imagine they'll be meeting again in the championship, possibly before 40029 is completed.
Either would be good. If just renaming and repurposing the Hex forum would save you a lot of work, fine. But if it's not much work, I think separate forums would be better.
The games have a fair bit in common, but they also each have a lot not in common. I don't think the player pool will be the same. I, for one, gave Hex a try and will continue to play occasionally but don't enjoy it nearly as much as Twixt.
But as long as we can post stuff about Twixt without feeling sheepish about cluttering up the general forum, I'll be happier.