New Vegas was great for a single play through. My problem with it was that everything was so centered on the main storyline and the game was structured in such a way that replays felt like you were living the movie 'Groundhog Day'. It had the least amount of replay value of all the listed titles, to me.
Cause it didn't have a sandbox map and the game steered you in a u-turn travel?
For me it's the complete opposite.
One playthrough in Oblivion and I had seen everything.
In New Vegas on the other hand I had tons of choices in quests and I could end it six ways: Caesar, Lanius, NCR, House, Independent and Greed.
In Skyrim I only did a certain amount of content before I ended my first character, cause I knew that if I had continued and done every quest then there would be nothing new for the next playthrough.
But with New Vegas, even if I tried to do every quest there would still be tons of choices and quests left for me to do.
So Oblivion, once I had finished the first playthrough, I took out the disc out of the xbox and put in something else.
With New Vegas, the disc stayed in for months.
So I guess it's all about what you consider great reaplayability.
For me it was choices in quests and dialogue. :fallout:
[edit]
Then again, for anyone that thought the gameworld was linear: http://fc03.deviantart.net/fs70/f/2011/186/a/4/nv_map__how_to_get_north_by_gabriel77cortez-d3l1vn8.jpg