I can't view youtube but I will comment on some stuff that I've read in the thread.
Gravity Gun - cool ass gun that deserves its spot.
Nukes - I agree nukes should be on there.  I loved nuking bases in starcraft with the ghosts.
Energy Sword on Halo 2 - that should not be on there ... that is one of the weapons in halo 2 that dummied the game down and a major flaw in the games design.  It would be okay if it was single player only, but for multiplayer it doesn't help, especially the fact that there is only 1 per level and the weapon respawn system in halo 2 is even more flawed.
Also after playing GoW, I would have to nominate the default machine gun for it's sheer fact  it has a chainsaw on the gun.  Anyone who's chainsawed someone in GoW on multiplayer can tell you that Chainsawing someone never EVER gets old.  Everytime I do it, it feels rewarding.  I'm almost going to throw it out there and say the Torque Bow should be on this list too 
