Have you ever played fallout 3? New vegas is nowhere near as good as fallout 3.
They aren't in the same league. 3 was good, but had no replayability after my 3rd character to max level. New Vegas, however, was a lot more story-based, and I appreciated that. Yeah, I know vanilla New Vegas was short, but I loved it's DLC over Fallout 3's DLC.
Well, that and the fact I've played the series since Fallout 1, so I appreciated the connected story.