Update - Subscribing to topics
Skylar I do not see a way to get notified when new posts are created, only when someone replies to one that I took part in our subscribed to.
You can now subscribe to tags (what we call topics or subjects), i.e. General Chat or Sustainable Living.
So, if you want to receive notifications anytime someone starts a new post anywhere, then you can just subscribe to all six of them.
You can find all of the tags listed here - Tags. Click on one, and in the page that opens which lists the discussions in that topic you will see a Subscribe button on the left. There are also a few other options in there as well depending on what notifications exactly you want to receive.