I think the easiest and most flexible way is to get the RSS of the category, tag, user or whatever you need, and then use one of the many plugins WordPress has to embed RSS feeds, and configure their presentation at will. This is what we are doing in our site and it works very well.
To get the RSS feed of anything in Discourse, just append .rss to the page you are at, and chances are that a RSS feed will appear. For instance: