Earlier quoted context omitted.
Just off the top of my head you know what I would like to see as an email interface: Reddit. Each headline being the suvject being an email with all the comments being the replies. Different users can reply in a threaded way to all the recipients of the message etc. Obviously it would need in-line attachements and in-line pictures. It would be interesting to allow a vote system on messages. Rather than file them, you…
> Each headline being the suvject being an email with all the comments being the replies. As in Gmail?
As cookingrobot says, gmails threading is one dimensional and super clunky when you have lots of replies. It auto collapses to far so you can't easily reply to a particular message in the thread.
Reddit has the best comment threading system of any site online. Quora is near the worst. HN is just slightly frustrating.