WhatsApp released iOS update 2.17.81 in AppStore (check here to see how this would look like in real world ;-)).
The update includes the previous announced improved voice messages. When recording a Voice Message, you can just swipe up to lock recording so you don’t have to hold the record button anymore.
According to the official changelog, another feature is the YouTube picture-in-picture (PiP) mode, we’ve discussed months ago.
When you receive a YouTube video link, you can play it right within WhatsApp. You can keep watching the video while you navigate to another chat. However, this option seems to be not enabled yet.