All art that pushes boundaries pisses people off and is bemoaned by the current generation of art critics. That's what art critics do - they bemoan.

A prime example is Van Gogh - he was unsuccessful as an artist while alive, but is now considered a master. Which, imo, is the most tragic thing about his life. Sure, he was crazy, but to pour that much of yourself out... and not just not get recognized, but get shat upon. The episode of Doctor Who which featured a fictitious account of Van Gogh made me cry for that reason.
Anyway, art is pretty much that quote Citizen found from Stanford. It's something created with intention. That's one of the reasons we have a hard time pinning down when the first art showed up in human development. Arrowheads and adzes were created with intention, but should toolmaking (a type of craft) be considered art? There are entire angsty threads on the etsy forums about this. Believe me, you don't want to get into that sort of discussion.
The thing is, I can recognize something as being art without getting my panties in a twist and having to put air quotes around it because I don't like it. I can separate my personal opinions about what kind of art I like from my slightly more objective critiquing of a piece of artwork. I don't actually care for most modern art (which, btw, is an appropriate usage - Modern art is a specific genre, but modern art is synonymous with contemporary art. Capitalization makes a difference.). I absolutely hate Rothko -
but I've learned that just disliking a piece of art doesn't mean it's not art.
andrew, btw, you've completely missed the point of art with your little "a computer can break it down and do it for you" rant. While it's true that I can paint with acrylic on my computer, it's a completely different skill set from painting with actual acrylic on actual canvas. For one thing, there are a million-fold more variables when working with actual materials - humidity, temperature, time, pressure, quality of paint, quality of canvas, quality of brush, etc. Computers can't simulate those sorts of things yet. I suspect it's the same for music.
Someone made an analogy about comics and literature. Well, lemme tell you, there is some absolute garbage literature out there and some damn fine comic strips, too. Calvin and Hobbes > The Scarlet Letter, for instance. Comics get a bad rap. So does a lot of contemporary art.
The problem is that art is a cultural thing, and as such, it gets taught to us. Making art is something that humans tend to do anyway, but the the form our art takes (eg, realism, surrealism, abstract, etc) is taught to us. We great Western peoples tend to favor realism. There are different kinds of realism, though; Greek realism is waaaay totally different from Roman realism which is waaaay totally different from Italian Rennaissance realism which is waaaay totally different from Rococo realism. Most Modern, Postmodern and contemporary art is a way of unlearning the habits we've had for the past few centuries and really figuring out what we can do. Art is so much more than realistically portraying a flower or a tree or a face.
The intention of the artist is more important that you'd think. Sometimes is helps to read why an artist felt compelled to dunk a crucifix in his own piss, or why he painted the eyes on the bottom of the face. It gives you a perspective. Art isn't created in a vacuum - it needs context. If you look at this:

and just see a pretty picture, you're missing
more than half the story.It's easy to scoff at something you don't understand. I get it - I used to scoff at art I didn't like because I didn't understand it. Studying the intentions behind certain art movements (such as modern abstract art) has gotten me over myself. Trying to imitate a Big Name artist gives you a bit of perspective, too. I've had to copy a couple of master artists now, and it's really quite difficult. One of my fellow students in my acrylic painting class made the decision to copy a Jackson Pollack for the Copy a Master project. She said, when we were presenting our final works, that she'd picked Pollack because she thought he'd be easy, but the opposite was true. Like it or leave it, Pollack had a technique. He developed it, and was master of it. His work is hard to duplicate for that reason. Most artists who are considered to be masters fall into that category - they are hard to duplicate. They have a style.
This has gone on for entirely too long, so I'll leave it here. Again, art isn't just the stuff you like. Art is all the stupid shit you hate, too, because hating something means that the artist got you to feel something and that's really all we care about - getting people to care about what we do.