"the ALT key is hardwired to HUD... I want that key bindable to something less widely used!"
Agreed.
HUD is a neat idea, if it works, but the thought of it "ultimately replacing menus" doesn't sit well with me. Standard menus (or even a version of the much-maligned "ribbon bar") should always be available for use, because:
-- -- 1. for some users, menus will be faster.
-- -- 2. for some users, contextual keywords for some commands may not be so obvious.
-- -- 3. for some users, keyboard interaction (typing) may difficult, and should be minimised.
-- -- 4. for some applications, contextual function access may not fit well with the app's purpose.
-- -- 5. for some applications, contextual function selection may produce unexpected results.
For those scratching their heads over the phrase "Sort of Ubiquity like..." in @keithpeter's original post (above): Ubiquity was a Mozilla Labs initiative to produce a context-sensitive task command system for Mozilla Firefox. Basically, it allowed you to select and manipulate web content through a natural language user interface. For example, you could highlight a real-world (postal) address, pop open Ubiquity, then type "map this," and Firefox would go find a mapping website to generate a map. You could then select the map and use Ubiquity to send the map to a colleague with the command "email this." I was surprised at how well it worked, at least in the video demonstration provided by Mozilla Labs. You can view the Ubiquity intro video here:
-- -- Mozilla Labs: Introducing Ubiquity
-- -- -- -- http://mozillalabs.com/blog/2008/08/introducing-ubiquity/