I enjoyed Fallout/Fallout2 tremendously and will definitely try Fallout3 which I missed.
Be aware that Fallout 3 (and by extension Fallout: New Vegas) is VERY different from Fallout1-2. Firstly it is more in the look of an FPS, although it is anything but. But the underlying story/game mechanics are merely updated and in the same vein.
Just saying that one of the big complaints at launch was from lovers of the first two (which I am) who thought it was a total betrayal of the original to switch from the isometric to the FPS perspective (which I don't).
Overall it is an Excellent game in it's own right. So don't judge it until you get into it and play around a bit.