Being a college professor, I often am asked by students (and parents) about the employment possibilities - and salaries - for psychology majors. They are asking the wrong questions. Choosing a college major should be about interests, abilities, and passion, not money.
I am at a college that makes it very easy to have multiple majors, some combinations that you rarely see at other institutions. For example, I have encountered several double majors in Psychology and Accounting (student explanations: "I'm taking Accounting for my parents, and Psychology for me;" "I want to be sure to get a job"). While there's nothing wrong with breadth in an educational background, it makes no sense to choose a career early on based solely on employment prospects.
There have been a several news reports of studies of the income and number of job openings associated with particular college majors. Psychology typically doesn't fare well in these because the number of psychology majors is high (it's one of the most popular college majors), and the number of openings for psychologists [and typically that title implies a graduate degree] is relatively small.
One recent report of employment prospects of college majors put an interesting spin on it, and suggests "tweaking" your major when looking for a job. That is a very good strategy and for one primary reason: Although most students spend countless hours studying psychology, they spend almost no time exploring careers available to psychology majors after graduation. I advise students to spend at least the same number of hours exploring psychology-related careers that they would spend on attending and studying for one college course (upwards of 100 hours).
The problems with most of these studies of college major job prospects are twofold: They focus solely on numbers (income and # of jobs); they focus primarily on the prototypical careers for each major (e.g., clinical psychologist or college professor for psychology majors). But, there are lots of jobs appropriate for psychology majors that, on the surface, don't seem to have a direct relationship to that major.
Take what I teach: Industrial and Organizational Psychology. Ph.D.-level I/O psychologists are employed in a wide range of jobs, from consulting to training and development to human resources and other areas, in addition to the traditional college professor (or business school professor for I/O psychologists). Many psychology majors come into my course thinking only of clinical psychology in terms of their career prospects, and their eyes are opened. "Wow, I didn't realize that psychologists could work in business! I've always felt that I've had a good head for business, but thought that major would be dry and boring."
One reason that psychology is such a popular major is the subject matter. We all want to find out more about what makes us tick, and why people are the way they are (you're reading Psychology Today blogs, aren't you?). Another draw to psychology is the helping nature of the profession, but there are many ways to help others in careers other than clinical psychology (e.g., I/O psychologists' common mission is to make workplaces better).
So here is the lesson to college students: Choose a major that interests you, one for which you are well-suited, and one that you are passionate about, but do your "homework" and seriously explore possible career paths, and the diversity of the field, before you graduate.