Effective immediately, posts can now embed one or more #tags into their body.
The topic/category is now the default and most relevant tag.
This post is now tagged with #steemit, it will show up under both https://steemit.com/trending/steemit, https://steemit.com/trending/tags and https://steemit.com/trending/steem (because the category is steem).
Be careful when you tag a post, because it more likely to get downvoted it has off topic tags applied to it.
If content is Not Safe for Work you should tag it with NSFW. Content tagged with NSFW will eventually be filtered unless the user opts to see it.