Fallout New Vegas is an attempt by Obsidian Entertainment to make something similar to the original Fallout games.
Obviously there are big differences between these games and I'll get to 'em soon enough.

Gameplay:
The most important part of any game. Fallout NV is an RPG game which allows you to have surprising amount of freedom. It doesn't force you to do any quests and most if not all of the quests have multiple ways of doing them. For example when you are looking for certain someone and ask info about the person in Novac you're asked to go and kill all the ghouls you find in REPCONN test site, you can:
1) Talk yourself out of it and get the info
2) Go and kill all the ghouls
3) Talk to the ghouls and ask them to leave
4) Pickpocket the person who gave you the quest to gain the info about the person you're looking for
Dialogue is fine but it could be better in some places. Fun thing to note is that the dialogue can chance depending on your characters stats (especially intelligence) and perks. Obviously you won't get quite as many dialogue options as you would in the original Fallout games but that is understandable since in this one all of the lines are voice acted unlike in the original games.
When it comes to combat it is essentially the same as in Fallout 3 but you can actually use iron sights without modding.

Enviroments and atmosphere:
Even though the enviroments for the most part weren't anything special the atmosphere is incredible. The ambient sounds and music really help make the game.

Music:
I do like the ambient music but when it comes to the radio.. I personally preferred the radio music in Fo3 but it isn't bad in this one either.

Graphics:
Pretty bland by today's standards but didn't bother me personally.

Story: At times it didn't make too much sense. Like right in the beginning. Anyone who's played the game knows exactly what part I'm talking about. It wasn't too bad overall and allows you to choose how you wish to continue the story with the small restriction of 4 major endings all of which are shaped more by some smaller actions throughout the game.
Basically without spoiling too much you can choose between 3 major factions or going your own way.

Bugs/Crashes:
This game was pretty infamous when it was originally released as it had some major bugs and would constantly crash but today I personally didn't experience anything too bad. I think I only crashed exactly once and the worst bug that happened was random bark scorpion spawning stuck in the ground and dropping through it or sometimes certain weapon related sounds not playing or keeps on playing until I shoot again. Thankfully most of the leftover bugs after the last patch can be dealt with by downloading bug fix mods from Nexus.

Overall it's a decent rpg and I would personally recommend it if you can overlook the minor things I've mentioned in this review.

I, king Harold of England, am a kind and just ruler. I was concentrating on family matters and ensuring better relationships between family members. So one day I decided to imprison my wife and excecute her so I could marry my friends heretic child.

10/10 best game.