PC Gamer talks to Senior Producer Larry Liberty, and we actually get some new and interesting info in this one: http://www.pcgamer.com/2010/09/24/interview-we-ask-obsidian-whats-new-in-fallout-new-vegas
Larry Liberty: I can say that there is considerably more dialogue in New Vegas than Fallout 3, and more overall reactivity. We made a change to the dialogue editor that allowed our designers to create hierarchical dialogues. It would have been impossible for us to write as much as we did had we not made the investment in the tool early in development.
Larry Liberty: I really like the Ballistic Fist – it’s essentially a tiny shotgun grafted onto a gauntlet. It’s activated by a pressure plate when impacting a target. Perfect for the unarmed fighters among us. Euclid’s C-Finder has the single coolest weapon effect in the game. It’s a space-based mega-weapon that has its own quest line. Spears are really fun for Melee fighters. We’ve added the ability to throw weapons, and in the case of the spear you can literally pin limbs to walls, with or without the victim. If you prefer a more traditional, conventional FPS weapon, the Light Machine Gun is fantastic. It has a high rate of fire, and with the right ammo type can handle most enemies rather easily.