You need to consider a few things when reading post on a thread like this.
First off, if you haven't noticed, the country (world?) is pretty much in an economic recession, with unemployment rates reaching historical levels (
http://www.google.com/publicdata/ex...seasonality:S&dl=en&hl=en&q=unemployment+rate). You will likely find un- and underemployment in any field- not just clinical psych. Unemployment tends to impact those newest in any field, as the end result is often more experienced people taking lower end positions. Graduating and starting a career during a recession is tough, but it's likely more of an effect of the cohort (or at least a cohort/discipline interaction), than it is an effect of choosing the field of clinical psych.
Secondly, like many careers, it can take awhile to get your career going. Graduate school/internship/post-doc, is just the beginning of your training. It is HIGHLY unlikely that job you get out of post-doc will be the job you're in for the rest of your life. You're probably don't yet have the skill-set for that dream job- it will take you many years and a few positions before you're qualified for the ultimate job.
Thirdly, recognize the bias with this sample. Overall, SDN members tend to be in training or early career- the very time when it is more likely to doubt your career choices, as you haven't yet got to the "pay-off" point. Additionally, many SDN posters are at the point in their careers that suck the most- the transition from formal student to purely on-the-job training (e.g. internship/post-doc). This is the point where you've been the longest removed from a real salary (and "real life"!). The reality of what those loans mean is starting to come to light. Within this already biased overall sample, these types of posts will be biased by the propensity of people with strong negative feelings to differentially respond to such a survey method. It's not surprising that many of these post are negative!
Fourth- you really don't know the truth about any of the posters. We just don't know if their inability to progress in the field or unhappiness about where they are is related to problems with their experience, training, skill-set, or expectations. For example, if someone undertook doctoral training in clinical psych at a non-funded, private, for-profit, 100 per cohort institution, took out six-figure loans to do so, all with the expectation of working as an outpatient counselor for private-pay clients, well... I would expect them to be totally frustrated regretful. Similarly, there may be details that posters left out that, if known, might make their struggles (or successes) make more sense. For example, in my career, I have interviewed several people for positions who didn't get the job, as well as fired/laid off a few employees. If you were to ask them why they didn't get the job/got fired, they would be more likely to say that it was a problem with the boss or with the system. If you were to ask me, I might say it was due to their insufficient skill-set or some other characteristic about them. Now, that's not saying that all negative posts are just complaints of deluded people with poor self-awareness (there really are some major problems with areas of clinical training, such as the internship imbalance). It's just that you don't really know what's going on when all you have is anecdotal information from only one side of the story.
You really can have a good, rewarding career as a doctoral level psychologist with a Ph.D. from a university based, funded clinical psych program. Current statistics suggest that your mid-career salary will average around 75-80K. My educated guess is that if you focus on generic, minimum standard to get the degree, "just do therapy" type of training, you'll require a lot of long hours and more than a bit of luck to attain that figure. If you focus your training on a good foundation in the basics of clinical science (including EBTs, valid/reliable assessment, research and statistics) and expand this to include specialty training and certification (e.g. neuropsych, forensics, applied behavior analysis, organizational/systems level clinical analysis), you'll
eventually (not immediately) do just fine. If, early in your training you find yourself needing to find training options that allow for experiential or skill deficits (e.g. poor GPA, low GREs, lack of any substantial pre-graduate school clinical or research experience), you might want to take that as a sign that things might be a little rough later in your career, and doctoral training might be an expensive and unfruitful decision.