Confidential transactions in bitcoin, as a soft fork:
One of the credible devs disputed whether it can really be done with a soft fork, though I'm skeptical that it couldn't. I don't remember whether it was on that list or somewhere else.
Anyway, I'll believe it when I see it. Bitcoin is mired in debate over every little thing.
EDIT: CT also does not keep metadata private. That is very important.
How much you donated to Terribly Racist Slighly-Left-Wing Party Inc. is irrelevant, the fact that your donation can be traced back to you by your boss, your government, your friends, your coworkers, is a Pretty Big Dealtm --fluffypony