the mods are what make bethesda games so great for PC gamers.
true the consoles has us beat on everything else, but i wouldnt trade my PC for a console ever for mods alone.
rest easy, as with the mass player made content readily available from fallout 3- Fallout New Vegas is gonna be hit hard with early created mods like no other game before it.
The problem with that is we are not allowed to use content from Fallout 3 in modding for New Vegas.
Recreating a Fallout 3 mod from scratch, yes that is allowed, porting a mod directly from one to the other isn't. If I remember correctly Bethesda have a long standing policy of not allowing assets from one of their games to be ported into another even if the game is a direct sequel.