http://fallout.wikia.com/wiki/Denver
In Van Burren there was a place called dog city which was denver. I read some stuff about it and I hope it'll become a dlc for NV who here agrees

A whole city is too large for a DLC, IMO.

Denver would need a full game to do right, and it's not a likely location for the next full Fallout game unless Obsidian gets to do it.

Would be awesome, and it *could* be done. Just look at The Pitt.

If you got a pc then there is a mod about Denver (including the dogs!)
http://www.newvegasnexus.com/downloads/file.php?id=41751
Just dont expect a top notch HH or DM experience, but as a mod it is very well done :goodjob:

The Pitt didn't take place in the entire Pittsburgh and Fallout 3 did not take place in the entire Washington DC.
So a Dog City DLC could, like The Pitt, use a certain area of it.
And not become too large.
And while I would like to see a game set in Dog City it's not very likely to happen.