Well, I just finished it and I can say that those people suck!
Just kidding. The combat will most definitely depend a lot on what level you are when you go in. I went at 24 and didn't feel too threatened by the enemies.
Furthermore, the stuff about the traps being unfair and all that... If you run into everything like a madman, then yeah, I could see how that might be. But Dead Money really encourages you to be careful and vigilant, and if you are, you should really have no problem with it. There was *one* section that I got annoyed with and had to re-load 2 or 3 times, but that was it in terms of the good ol' "having to go back and try again".
That said, because it *is* a very "survival" type of gameplay, I don't think I'll replay it anytime soon because... Well, a lot of the tension comes from a first impression type of deal I think.
On the other hand, the companions, story and backstory presented here are really top-notch. You can definitely tell that Avellone wrote this thing, there is quite a lot of dialogue and text (especially considering that this is "just" a DLC) and seemingly a few different ways you can handle companions and the main quest. And quite a large number of skill-checks as well, featuring some skills that are not used too much in convos otherwise. There is also an ending slide for the DLC similar to the main game, though obviously a lot smaller in scale.
If we are to compare to the Fallout 3 DLC, I think this one easily trumps them in terms of quality. Point Lookout can compete in terms of quantity and things to do but it's hard to compare since they are rather different in design.
This is the only time, along with Mysteries of Westgate, I felt somewhat invested in a DLC of any game and much of it has to do with really great writing and the tense atmosphere.
Still, while there are a lot of tie-ins to New Vegas itself, older Fallout titles, and even lots of hints for the upcoming DLC for the game, it still has that DLC feel where... Well, it just feels like a separate thing you know? It feels as if your character steps into another dimension for a spell, and then returns again.
But yep, I certainly enjoyed it. Of course, if one has other games to play I'm sure there'll be an ultimate edition down the road with all the DLCs and all that packed together.