Originally Posted by NarcissistZero
Not at all I would guess, the mods and mod tools work fine with Fallout 3 on Steam. The official FAQ says New Vegas will have the same mod tools too.
I was kind of hoping this would work like Rogue Warrior, where you could have an offline install without the Steamworks features, but the official New Vegas FAQ now says Steam activation will be mandatory.
Well that's good to know. I could not tolerate playing FO3 if I didn't have my PC adjusted menus/inventory/HUD/FOV/high res textures/etc..