I've heard it said of Skyrim that it's a mile wide and an inch deep. You could perhaps say the same for Fallout 3.

That being said, Fallout 3 is better for exploration, but New Vegas is better for story based interaction with the world. Fallout 3 probably has more and better locations, but it's a set of disconnected set pieces. I found it interesting that Crop liked that, but in reality if you did live in a warzone like that, all the talk would be of NCR vs Legion. Or indeed what the Enclave and BoS are doing in the case of Fallout 3.