Just beat the game, and YOU DON'T EVEN DIE!!!! And you STILL didn't get to continue playing. In my ending, the NCR completely takes over the Mojave Wasteland... and Caesars not even dead. Furthermore, I WANT TO JOIN THE NCR RANGERS. I hope your listening, Obsidian... you better fix some things.

The game ends because the the various endings you can get affect the world far too much to allow you to play further. Even if Obsidian did make a DLC that let you play further, it would be a massive amount of work because there are dozens of different endings, with 4+ potential endings for each major faction (see for yourself in the GECK), and they would have to make the DLC reflect every single one of those endings. It'd be a huge undertaking that probably couldn't be done well anyway.

The game clearly warns you when the ending is closing in. Simply make a save before the mission and then continue free roaming.

Wait... so future DLC's coming out won't further the story? Damn! That svcks! What will the DLC's be about then?

I bet they do make a Broken Steel Type DLC though. Maybe raise the lvl cap to 40 or 50. But my question is this:
How will they possibly make it so you can continue playing on? Like the above poster said, the endings would change the game world so much.

We'll see I guess, but even if they do I won't be able to play it for at least a year, as I am a PS3 player...

Think that's bad? My ending has caravans dying, most of my companions dead and Power Gangers taking over...

(modded to keep playing, and level cap at 150)

They won't.. at least I hope so. Because the amount of work needed to do this will mean the DLC will:
- Be really expensive, due to the amount of work/time invested.
- Be really short, see above reason
- Feel half-assed, like Broken steel did to the Capital Wasteland

They might raise the level cap but the ending will most likely be the same and stay closed (unless someone mods it out).

The warning covers everything pretty much and the ending doesn't (to me, at least) as anti-climatic as FO3's did.

Your. Story. Is. Over.

That's why it ends.

Why is this concept so foreign?

BUT NO VIDEO GAME I'VE EVER PLAYED BEFORE HAD AN ENDING!!!!!!!!

Oh wait, 95% of them did and the other 5% became completely irrelevent within an hour post-ending or are Fallout 3 or GTA4.