Yes, you can sort posts. By default, posts appear in the order of most recent posts at the top of the feed.

Just above the first post, you'll see a drop-down menu that shows: Filter By: Most Recent. Clicking on this displays the filtering options, which include Discussions, Cases, Referrals, and News.

The sort options are meant to represent the categories of posts you can create.

In addition, all posts are tagged with one of these three post categories. As you can see below (notice the Referral tag). This makes it quick and easy to go through posts about the topics you're most interested in.