A lot of site members want the ability to upload a "story" which is basically a short video that displays for only 24 hours on their profile, and in the site's "stories" section before deleting itself.
The option to set the story length limit (example: 1 minute), the expiration time (example: 24 hours) and usergroup settings to enable/disable for different groups, would be great.
This could be a core app, or a separate app. Either way, with the function available on the big networks, site members will be looking/asking for it on our sites too!