Okay so to get this out of the way you can not "continue" the game after the last mission & credits i.e. like you can in Fallout 3 if you have the Broken Still DLC 
 
Obsidian has said they will not do a DLC that continues the main story like Fallout 3 placing you back on the world map after the original ending cause of how they built the core games story it just defeat the purpose of aspect that make up New Vegas
 
Alright so a work around would basically allow via a DLC to allow you to simple put use a >New Game Plus< feature when you select this option you'll be ask to choose a previous save does not need to be a specific save it can be any so if you have a level 15 character for example I would start my >New Game Plus< with my total skill points that where earned to be used right off the bat as well as my caps on the side 
in addition you would have all the ammo or anything that does not wight anything on you
but the cool thing is all the location you had been to would be marked on your map and ready to fast travel to right away

make a save before you do the last mission?  

" Okay so to get this out of the way you can not "continue" the game after the last mission & credits i.e. like you can in Fallout 3 if you have the Broken Still DLC   Obsidian has said they will not do a DLC that continues the main story like Fallout 3 placing you back on the world map after the original ending cause of how they built the core games story it just defeat the purpose of aspect that make up New Vegas  Alright so a work around would basically allow via a DLC to allow you to simple put use a >New Game Plus< feature when you select this option you'll be ask to choose a previous save does not need to be a specific save it can be any so if you have a level 15 character for example I would start my >New Game Plus< with my total skill points that where earned to be used right off the bat as well as my caps on the side  in addition you would have all the ammo or anything that does not wight anything on you but the cool thing is all the location you had been to would be marked on your map and ready to fast travel to right away "

" @ShinjiEx said:

" Okay so to get this out of the way you can not "continue" the game after the last mission & credits i.e. like you can in Fallout 3 if you have the Broken Still DLC   Obsidian has said they will not do a DLC that continues the main story like Fallout 3 placing you back on the world map after the original ending cause of how they built the core games story it just defeat the purpose of aspect that make up New Vegas  Alright so a work around would basically allow via a DLC to allow you to simple put use a >New Game Plus< feature when you select this option you'll be ask to choose a previous save does not need to be a specific save it can be any so if you have a level 15 character for example I would start my >New Game Plus< with my total skill points that where earned to be used right off the bat as well as my caps on the side  in addition you would have all the ammo or anything that does not wight anything on you but the cool thing is all the location you had been to would be marked on your map and ready to fast travel to right away "

They also said Fallout 3 would not keep going after the main story. And look what happened.  "

I'm not done with the story quite yet, but from what I've played so far, it seems like a hard ending would make more sense for New Vegas than it did for Fallout 3.  The three factions seem to have a pretty big impact on how the world changes over the course of the game.  I think it'll be more fun to restart and play things out differently.  That said, I do hope that they throw in one of those things where they tell you that it's time to save your game and get ready because there's no going back.  That way we can still get our exploration fix.  It would be nice to not have to redo the walk of shame through every playthrough though, definitely eats up time.

" make a save before you do the last mission?   "

Ohhhhh.... i think they'll change their mind.  It's not like big companies to lie for marketing but.... we can only hope.

I really don't think games like this need to have a new game plus. I always just roll a new character if I want to play more.
In Fallout 3 I spent most my time with it before the Broken Steel DLC, and every time when I hit level 20 I just plowed through the rest of the story and then made a new one that I build and played in different way.
You can build characters in quite a few interesting ways in Fallout, and with the return of the low intelligence dialogue in New Vegas there's even more ways that could be fun.
I'm currently playing through with a fairly standard high intelligence characters that specializes in guns/repair and lockpicking/science, but I can't wait to play with someone with high speech or a low intelligence character who just wants to hit things with a tire iron.
I've been wondering about how a low intelligence character with high charisma and speech would play as well.
 So I don't really feel the need to play through it with the same character, because there's so many ways to play it would feel like a waste to spend all my time with just the one.

I absolutely, positively, could not imagine playing a character with a low intelligence/speech attribute.  It seems to me that you can practically talk your way through these games.  I've yet to encounter a situation where having a high speech attribute didn't grant me some sort of bonus.  It's probably the most important attribute, IMO.

" I absolutely, positively, could not imagine playing a character with a low intelligence/speech attribute.  It seems to me that you can practically talk your way through these games.  I've yet to encounter a situation where having a high speech attribute didn't grant me some sort of bonus.  It's probably the most important attribute, IMO. "