Having never played either Fallout 1 or 2, I'm basically starting Fallout 3 oblivious to the inside jokes and references that Bethesda has included in their latest game. But that hasn't stopped me from enjoying what I've played so far! Coming from Bethesda, the game definitely reminds me of Oblivion in terms of the feel and UI. I remember seeing screenshots of the earlier two games, and I'm glad they chose to move from the top-down-at-an-angle perspective to first-person.
One thing I liked off the bat was how they integrated the character creation process with the storyline (if you haven't played it yet, you'll see what I mean). It gives it more of that RPG feel, but I sense it could get annoying after multiple game starts. The first level, Vault 101, is your typical get-to-know-the-game type setting where you're expected to do quick and easy missions in order to familiarize yourself with the UI and game mechanics. I also noticed that the game responded to your situational decisions offering multiple paths for different choices. If you kill a particular person, the storyline is somewhat affected and that gives a good illusion of non-linear play. I haven't gotten too far yet so we'll see how far that "non-linearity" goes further into the game. I didn't have much time to play, so I stopped about when I reached Megaton, a main city in the game outside the vault in the wastelands. Hopefully this weekend will give me more time to mess around and try things out for a better review.