Feature Request: Direct Message Preview

I'm sure many other people have encountered the problem of information within direct messages wanting to be kept personal, whatever that may be, to the people around them. So perhaps something similar to the server population preview when you hover over a server icon could also be implemented to direct messages.

If it's text it'll give you a small preview that would be harder for people around you to read, or if it's an image it will give you a warning such as [Image] or *Image Attached* when you hover over a direct message.