I think interest is somehow more important, provided you can survive with the salary.

High salary, but the work is damn boring and you totally do not have any passion in it. How you develop it as your life career?? And when you no passion, no interest in your job, most likely you wont do a good job.

Interest, you like your job, and you willing to dedicate yourself into it the correct way(not by blindly addicted to a PC game, eg). Nothing is wont have much future. The sky is the limit, it is up to how you develop yourself.

Then again, when you do your interest in your free time, its fun, when you get serious about your interest, your interest might start gets boring...