Once I heard him mention the Weeping Angels, I started nervously laughing. I just realized how terrifing these things will be. Endermen will probably be bearable if:
1.) They are very, very rare. Just a little bit more common than lava pits aboveground.
2.) They are succeptable to sunlight, or have a weakness, like wood or gold shovels.
3.) They shouldn't spawn in packs.
4.) They should drop something really, really good.
5.) They shouldn't be provocated through windows.
Or, instead of all of those,
-1.) They should only appear on the "normal" or "hard" difficulty settings.
Yeah... whatever happens, minecraft is going to change quite a bit due to these new monsters. It probably won't affect me, because whenever I see a monster underground I turn it on peaceful...