seems like cactus/succulent gardening is a diverse, yet distinct, enough plant classification to garner its own forum. tons of people keep tons of different varieties of jade, aloe and cactus, that it would make sense to be separated.
Here's a discussion that took place in January of this year on the same topic. I know that the webmaster has been working a lot on behind-the-scenes stuff to keep the forum running smoothly during this "crunch time" of the year, being peak planting/gardening season. I don't know whether he plans to add/subtract any forums after the crunch has abated.