Both Windows and OS X have conventions in place to help with discoverability.
Windows menus items have certain letters underlined, and you can hit Alt+underlined letter to open a menu, then Alt+letter to select an item or submenu. It provides both discoverability and keyboard-based navigation.
OS X places hotkeys at the far right of every menu item which has a hotkey equivalent.
sure, discoverability. I guess what I want as a user is for Excel to tell me, "you're formatting a lot of cells the same, have you heard about format painter?" ... though as Clippy that was a little obnoxious.
That would be great. Do you know any other apps (other than emacs, that is) that provide a similar sort of discoverability? And on the similar note, is there a way to make emacs's tips be even more prominent?