There are art snobs who want to make you feel bad for liking a painting just because it's pretty, but history is made -- be it art history or family heirlooms -- because people save the things they love, and objects of beauty often rank high on that list.
So what is the difference between wall decor and contemporary art? Probably a lot of answers would focus primarily on price point, but that's too easy a separation and addresses only the monetary value.
Let's define an artist as someone with the ability to embed thought or feeling in material. This explanation might sound abstract at first, and yet we invest inanimate objects with power every day: wedding rings, dollar bills, etc... Art isn't just a reflection of status, it speaks to our self-expression and sometimes even to what we value personally.
As a little kid, my family had a Robert Indiana LOVE poster in our hallway. He's not exactly my favorite artist, but the image has always stayed with me, and so now whenever I see another version of that piece (and there's a big statue of it here on 6th Avenue in New York) I think of my parents and my late sister and it brings me back to childhood.
So you see, it's not only artists who embed ideas and feelings in material: viewers do, too, and the bond we create can become a new form of content in the painting or print which didn't exist before. Context is content!
Many of the pieces I live with now were acquired to mark an occasion or because it reminded me of a connection in my own life. Sometimes you buy a picture because it keeps you smiling.
The first real art I ever bought was a Terry Richardson photograph of a clown flipping off the camera. I used to keep it in my foyer so whenever I opened the front door at night it was like a ridiculous "welcome home" greeting. Of course, now that I have two kids, the clown isn't up anymore, but he lives in my closet and will forever make me laugh at the folly of my bachelor days.