What I really hate is when people call me a hobbyist when it comes to writing. I don't know what you readers think of when you're called hobbyists, but I think of someone who just does it for fun, who has no desire to do anything with it. That's what photographers are called when they don't plan on doing anything with their photography--hobbyists. I'm considered an advanced novice because I do plan on doing something with my photography.
I'm not belittling hobbyists in any way, but for a girl who has published before and is still seeking more publication (plus an agent), being called a hobbyist grates my nerves. In this sense, it has a negative connotation. True, I may not be making a living off this, but that does not mean it's my hobby.
Obviously, I'm going to seek work when I'm out of college and not make writing my main job, but that does not mean I would ever consider it a hobby. A hobby is something you do in your spare time, and I DO NOT write in my spare time. In fact, with writing and everything else on my plate, I have little spare time. If you are serious about getting published, writing should never be done in your spare time in the first place.
Now to clarify, there is nothing wrong with being a hobbyist when it comes to writing. Even those who consider writing a hobby can still offer great insights into the world of writing. They can still make fabulous beta readers. They can do everything we writers-who-seek-publication can do.
But if you're serious about seeking publication (even if you're not thinking of publication because writers tell you to never think of it when writing your first novel), don't call yourself a hobbyist. You're just a writer with a dream. Not a hobbyist.