Titanium: After they simplified the alignments in the 4th edition, I didn't really care too much for it anyway.
When the inevitable reboot hits, we're going back to the roots, that's for sure.
AFnord: I never bothered with alignments in the first place. They felt like such an artificial character restriction.
Well in theory they were supposed to be a guideline for how your character behaved... more like a description than a code that had to be adhered to constantly. The whole alignment system was never treated consistently, though, so in various books over the years you got wildly different descriptions and thus, wildly different player interpretations.
I mean, the original True Neutral description is the "must maintain balance at all costs" one, which includes IN THE DESCRIPTION a character who changes sides in the middle of a battle once one side gains the upper hand. So essentially a career traitor... good job guys. This is the description they used in Baldur's Gate, too.
And then there was the change between Law/Chaotic affecting how the individual integrated into society, into the character's personal code. There was always some overlap in the olden days, but in 3e or 3.5 it was changed so that as long as you always stuck to your guns and never compromised, you were Lawful... even if your personal values were "chaos, destruction, and entropy."
tl;dr Alignment has the capacity to be a good system but it needs competent writers, players, and GMs. (Which it hasn't always received.) And don't get me started on the Paladin Code, either.