"What Is Art?"

It's a popular philosophical question.  "What is Art?".  It's how the occasional professor starts their somethingorother 101 class in front of a bunch of doe-eyed college freshmen.  Freshmans?  Freshmens?
At any rate, it's one of those things that eventually becomes someone's tweet of the day, or a great way to spend/waste the first day of class (depending on how things go).  It's why, if you're a music major, you'll start just about every other class discussing John Cage's 4' 33".  Because inquiring minds wanna know, what is art?
It's become a sticky thing, as institutions are built around this thing some people aren't even sure exists.  Some call it a process, a destination, a journey, a product, a lifestyle, the list goes on and on.
I feel on the fence about the whole idea of even debating this.  Part of me finds it interesting to talk about, as I learn about perceptions, the other part of me finds it ridiculous to waste so much time speculating about something a lot of us just intuitively identify with.
But, I KNOW what art is.  See, while a lot of the discussions above seem to be about what THINGS should be classified as art, it's become really simple to me what ART is, regardless of what THINGS are classified as it:
Art is a carrier.
Music, literature, visual art, architecture, even fashion, (and certainly, other things I missed).  They carry ideas.
I saw a really interesting TED talk with J.J. Abrams once where he talked about his brand of film making and what movies are "really about".  For instance, how Jaws is about a guy who's gotten a divorce and is finding out what it really means to be a man, and not a giant shark.  (I wouldn't know, as of this time I've never actually seen it.)
Or here's one I can talk about off the top of my head, The Incredibles is about how we can be great, have dreams and be extraordinary, which doesn't have to be mutually exclusive to having a healthy family or a practical existence as well.
Music carries ideas.  People listen to songwriters "say" things to them all the time that they'd think was bogus if one of their friends said it, but because it's couched in melody, it's easier to swallow, or even "ignore".
And the deeper you get into an art, the more you learn this is true.  In music, you start getting into history and reading stuff where people have analyzed instrumental pieces for orchestra and pulled all kinds of philosophical and psychological stuff out of it.  Visual artists and graphic designers learn about color theory, subject matter, etc.  Writers embed allegories, references, and isms at every turn.  It's not just about telling a neat story.  Screenwriters, I tell you, when you're watching a movie you can almost feel it coming, that pivotal moment when the music stops just long enough for a character to say that one line, that one thesis statement for the whole movie.  Man, even video game producers....where else can you get someone to spend 10+ hours with a character?  You can tell a lot of stories and push a lot of ideas with that kind of time and emotional attachment. 
So art is a carrier of ideas.  It is a comfortable syringe for messages.  And so much good can be done with it.  The thing we need to ask ourselves when we go to create something is, "What's the message this is going to bring across, and is it one that needs to be sent?"  And when we're exposed to art, we should ask, "What's this trying to say to me?"
A lot of people don't want to believe this, but this is how industries are built.  If you want to penetrate deep into the heart of the "educated" artistic community, you get technically up to snuff, or find a bunch of people who are, do something a little avant-gardy, and there you have it, an audience that may elect to give you a title and a grant.  If you want to get your message out to a larger, but somewhat less discriminating audience, you use popular music or hollywood film as opposed to sound-paintings or documentaries (not that some people don't like a good documentary, but you get the point).
I can get you to believe that all men are pigs if I break your heart enough times onscreen or in a book or a song.  Or I can get you to believe in heroes if I show those to you too.  I may not even have to say "heroes still exist", I'll just show them to you enough times.
So to me, since art is about a message, then the message is a big part of what determines the worth of the art.  Skill is great and everything, but that's not enough.  Too many times people have skill, but don't know what they should say with it, so they just find someone who is impressed by their skill, and use that ability to work for them and convey THEIR message.  That's great sometimes, but other times it may not be.  We sometimes call something "good" just because it's well-done, but the message might be sketchy at best.  So then, is it good?  That can feel like a tough question to answer.
So this is something I think about.  Because I can hardly watch a movie or play a game or listen to a song anymore without immediately figuring out what it's really trying to say to me.  And I'm surrounded by people all the time at school who can basically do the same thing, it's their class assignment to do so or even the subject of the day's joke.  Because after a while, the subtexts don't seem so "sub" anymore.
Hm.  Well maybe I went a little deep with that.  But there it is.  Art is a carrier.  Different things may be classified as "art" to different people, but that's because to them, it carries a message.