It has been said that the benchmark of RPGs is Bethesda's The Elder Scrolls IV: Oblivion. Although I would not go as far as to say that Fallout 3 is better than Oblivion, it does have a very distinct charm in its own right. Put simply, Fallout 3 is awesome! The game has a "sandbox" format, meaning that your character is essentially dropped into a meticulously crafted world, and is set free to do whatever he pleases.
When you step out of the Vault 101 bunker, you see an expansive nuclear wasteland, and you essentially point your player in any direction to begin your journey. There are no demanding goals to achieve, no forced objectives. The survivors you meet along the way will vary from the most kind, gullible of creatures to characters thirsting for your belongings and doing whatever it takes to separate you from them. Interact with them however you'd like. Each time you play the game, you can walk away with a completely unique experience.
For example, my first character set out to be a knight in shining armor by saving the world! He wandered out from the Vault and discovered a refugee camp inhabited by a sect who worships an undetonated atomic bomb at the center of the city. He disarmed the bomb and as a result was revered and thus showered with praise and gifts from the locals. In time, my knight became a savior of the Wasteland, freeing slaves from wicked raiders and becoming a guardian of a group of orphaned children who were hiding out in a cave.
My second character was the complete opposite. He would get into fistfights with his childhood friends while growing up in Vault 101 (you begin the game as a three year-old, crawling around in the vault and then play as an adolescent in the game's tutorial). When he left the vault, his evil nature flourished, because the Wasteland is a world without rules. He ran into the same refugee camp and met a mysterious man in the camp's saloon, who offered him money in return for one, little errand: To detonate the bomb in the middle of the camp. He did. He went on to become a slaver, making money by selling innocent lives in order to pay for his rampant alcoholism. Whenever he got hungry, he resorted to cannibalism.
Both of these characters became who they are because of my decisions I was forced to make while wandering arbitrarily in a huge Wasteland.
But this is not your typical RPG. It incorporates FPS elements seamlessly. Taking down you enemies can be done from an awkward third-person perspective or tackle the game the way the developers seemingly envisioned it, from a first person point of view. Your character is highly modifiable. Since Fallout 3 is an RPG, there is an experience system complete with skills, attributes, and perks that you may choose upon leveling up. There are also decisions in the game which affect your karma (essentially how people perceive you). All these elements provide a great level of versatility in how you shape your character.
The learning curve is about average for your basic RPG. Like most games of this genre, the hardest parts are just memorizing what specific items are and how they relate to your character. Such things as V.A.T.S., caps, Med-X, Mentats, Rad-X and Psycho (to name just a few). But like most RPGs, the understanding of how each of these things work, as well as how and when to use them, will naturally come to you through normal gameplay.
There are a ton of different weapons to make and collect. Using them requires that you continually maintain and upgrade them which encourages you to search through ruins for ammo, weapons, food and other essential and non-essential items. The variety of weapons in Fallout 3 will make even the most hardened soldier get teary-eyed with joy. There is an assortment of enemies to conquer, so you'll never have too much peace and quiet. From animals (both normal and mutated) to fierce humans and even aliens!
The graphics in Fallout 3 are bleak, disturbing, and yet at the same time wonderful. To ask for a game of this size to have graphics that could match its enormity would be quite an undertaking. Yet a task Betheseda was apparently up to. In Oblivion, nearly every cave had a familiar feel to them, giving the player a deja vu sensation as they enter. Not so with Fallout 3. Each territory, every building, all rooms have their own unique design. Since Fallout 3 takes place in the United States (obviously in an apocalyptic future USA), there are landmarks that are highly recognizable, yet distressingly dilapidated. These elements all help to make the game come to life!
Another huge positive of Fallout 3 was the voice acting. It was exactly what one would expect of a title from Betheseda. Liam Neeson is the voice behind your father. Ron Perlman (of Hellboy fame) does the "War" introduction. Fine voice acting is nothing new for Betheseda as Oblivion also was well above average in this category. The ambient noise however, would be where the audio shines. While wandering around a barren, lifeless and lonely wasteland, the obvious noises (or lack thereof) are what makes those abandoned moments memorable. Be it the haunting quiet of a gentle breeze, a gunshot heard in the distance or the hellish silence from your forsaken situation causing you to tune into the local radio broadcast and listen to the mono recordings of a song made long ago. All of these sounds immerse you in the deserted world of Fallout 3.
If you have a PS3, XBox 360, or a gaming PC and have not given Fallout 3 a try, you are doing yourself an injustice. For an RPG, Fallout 3 is an absolute must-buy. Even if the genre isn't what you normally consider while choosing a game, chances are you will probably still find this game highly engrossing.