An honest and concise opinion from someone who has completed the game.
I decided to play conservatively and complete the game without doing every quest and exploring every nook and cranny. If I had I know I could have put another 50 to 100 hours into the game. It's huge and there is plenty to do and see.
What I loved:
-More of what made Fallout 3 great! A Pip-Boy, the combat (V.A.T.S), the atmosphere, the enemies, the ability to interact with just about anything, the people who populate the world, the war torn environment, and the exploration.
-This game has more weapons and armor with the ability to make modifications to the weapons or change ammunition based on the enemy you are fighting (an enemy with armor or no armor).
-The wasteland sounds with the radio turned off fit the mood quiet well I thought. It felt melancholy and sad, just like a post-nuclear disaster world should be.
-The reputation system definitely makes every choice you make important.
What is okay but nothing special:
-The Pip-Boy music is back, but the music is not as good. Plus, I felt cheated that with a game so huge the production team couldn't put a few more songs into the mix. Mr. New Vegas is not Three Dog!
-The ability to create items from work benches, reloading benches, and campfires was neat, but I felt that I could get all I needed by just exploring. Not really a complaint just my own personal preferences.
-New Vegas didn't feel as special to me as Fallout 3. The Capital Wasteland was more fun to explore.
What about the bugs?:
-I played 55 hours and had a few problems. Many reviewers make it sound as if an exterminator is needed to handle all the bugs, but in my opinion a can of Raid would be sufficient.
-The game froze on me 3 times with a complete re-boot of the 360 needed.
-I didn't feel like my companions followed the advice on the companion wheel at all times. It was nothing major, but it could be a little annoying.
-Certain quests were confusing or didn't work quiet well. One person that was supposed to follow me would not follow me from one location to the next. After another 5 hours of gameplay the character showed up out of the blue during a completley unrelated quest.
-At times, in the first person view, my arms would go up and down with the weapon I was holding.
-I saw enemies and people get stuck in the environment and not be able to move. Example: A Gecko's head and arms were sticking out of a rock, but it couldn't attack me. A Bark Scorpion's tail was sticking out of the ground, but it's body was trapped in the ground. People sometimes were walking into each other or trapped inside bar counters.
*None of these problems seriously detracted from the value of the game in my opinion.*
What I Hated:
-Nothing!
I have no qualms in recommending this game to anyone. If you enjoyed Fallout 3 then there is no reason to not like New Vegas.