Nawzil has posted above screenshots on Twitter, from a latest version of WhatsApp Beta and with option of Media autodownlaod. Seems, this feature will soon come to WhatsApp. As seen in the above screenshots, there will be lots of options to control when to enable or disable autodownload. You can choose to download on WiFi or on mobile data and also what to download on mobile data. Roaming download options are also there. Here is the tweet from Nawzil,
Media AutoDownload options coming soon! #WhatsApp beta for #WindowsPhone. pic.twitter.com/rjqFoOv20d
— Nawzil (@Nawzil8) January 24, 2014