It's been in the process of bucket kicking for a little while now. These days it's really the place for mods, sometimes maps, and resource packs. I suspect discussion has died down so much because the community is so vast and the game has been out so long. This tied with the rise of social media putting a damper on places like conventional forums has really made an impact on the place. Plus, Minecraft isn't in its Beta days anymore. There's plenty more places to follow the game's development now.
But I hope this place never goes down. This forum holds many relics too precious to lose.