When I played fallout 3 for 360, (with all the DLC), after a wile my saves...or somthing would i guess get corrupted, basically the DLC (sometimes more than 1) would not load, and it would come up with that messege saying the DLC is no longer available, asking if i want to continue anyway.

So im just wondering if this problem will eventually happen in new vegas with the bonus content.

We don't know, they won't answer, and if they do they'll say they've noticed the issue.

Conclusion: wait and see.

Since it's no longer hidden behind layers of convoluted GfWL mechanics and programming, I'll say this at least won't happen as often anymore.