When ever the devs talk about the ideas they got from mods in FO3 they never fail to talk about hardcoe mode and wepon mods, but is there anything else beyond that. im sure there was thousands of mods in FO3 but they only pick those 2 to add in NV. I guess what im trying to say is, is that the only 2 new main game changeing elements they added or are they holding someback till release.

hardcoe Mode and Weapon Mods is just one of many, MANY improvements and extra features.
For instance, the new companion wheel, the new dialogue system, traits are back.

There is lots of "new" things, you just didn't look at them.