I'm one of the few people who thought Dead Money was awesome. I had tons of fun playing it. Interesting plot/characters, lots of extra features across the board (new levels, perks, weapons, etc), and it has a bunch of hints for future DLCs too.
I think it's kinda meh, but mostly because it followed the Knoxx DLC which was amazing. Overall it's not that bad, it's a step backwards IMO. It's comparable to Zombie Island, basically nothing amazing but if you like the game it's enjoyable just to get some new areas and such