I have it but don't use it.
I don't really use it except for with creatures cosmologically defined by it (angels, demons, etc.). I enjoy throwing some light moral conundrums at the party, but I don't find the neat little 9 boxes that no two players quite conceptualize the same way a useful construct for facilitating much of anything. Someday I might use an alignment restricted magic item if it is useful in making it clear which party member it is intended for but it hasn't happened yet.
I still have alignment because it is on the standard character sheet, players expect to have it, and I don't want to get into debates about alignment. If a player wants to play to their alignment (and they aren't a jerk about it) then more power to them. If a player never bothers to write anything in the alignment line then more power to them. If players want to have a whole alignment debate, fine. I'm not paying much attention as long as nobody is being picked on, and I'm always happy for a break to prep the next thing.
When I helped kids make character sheets at Summer camp I never bothered with having them write in an alignment unless they asked about it, and actually continued to be interested when I explained the alignment system. One kid wrote "Smart" for his alignment, and I thought that was pretty great.