Fallout 3 or Borderlands?

[natowarhead]

I've recently received a gift card to a local gaming store. I've been meaning to get another game for a while now. And I've had my eye on Fallout 3 and Borderlands for the PC.

I don't have much extra money these days and, to be honest, want to make a purchase worth my while. And there's just enough on the gift card to get either game, but not both.

I've read reviews and seen videos of both games but still am not able to make a decisions.

Any opinions on which one would be good? I'll take any comment into consideration.
I don't want to start a competition between the two games. Basically just looking for information that's not apparent from reviews or video clips on youtube.

Much appreciations in advance

P.S.

If it helps, my background includes:
- A LOT of World of Warcraft (quit it a few months ago after finally killing the Lich King)
- some Unreal Tournament (not good, but decent)
- A little Team Fortress 2 (I'm more cannon fodder than anything, but I like playing)
- A few Diablo clones ( I <3 RPG's)