Integration of data features
I've mentioned the fragmentation of apps before; if you wanted to make something that would be genuinely useful to many businesses and allow for some great productivity leaps - here it is. Combine Forms, OneNote, Infopath and a Sharepoint Webpart into OneNote - effectively removing the overly complex, unfriendly and rather unfairly forgotten infopath.
Example shown on the link below.... it uses no new features as such, is more powerful than forms, totally replaces infopath and provides a powerful sharepoint interface.
Can't see the link? All I can say is that external sharing is enabled in my admin settings.... but we can't post screenshots or upload a picture to the onenote feedback forum :)