I will give you my opinion as well. I agree with what has been said already.
What personality traits are important to succeeding in the ATC specialist’s job?
Type A is typical, but I've seen all types of personalities be successful. Obviously attention to detail and keen observation skills are important.
How sedentary is the work environment?
Depends...in the Center, we sit all the time for our jobs.
How long is a scheduled work day?
As stated previously, 8 hours. 10 hours is the max allowed by law. 8 hour break required between shifts, but typical shifts in my experience are two eves, two days and a third day or a midnight shift.
How much interaction is there with co-workers? Is going to work a social experience or are you left alone to interface with transponder readouts?
A lot of interaction between co-workers. As stated, definitely a team sport.
How routine is the job; is there much variety between days, or is one day just like the next?
Flights operate on schedules, so many days turn out similar to another. Weather, military, and special events change the mix so you get a wide variety between your average day.
For people who get into the job and hate it and end up leaving, being terminated, or do poorly at it are there any common denominators?
ATC isn't for everyone. Some people get into the job merely for the money and benefits, but hate the job because it just doesn't match up with their personality. They are not comfortable with the adrenaline rush, don't like the pressure to make so many decisions. The other type that doesn't do well is the person that doesn't take the job seriously, doesn't study or put in the extra effort, doesn't ask questions. They don't do very well as a rule.
How about "burn out", what are the leading reasons given for career burn out (if any). In facilities where overtime is routine, it causes burnout in a hurry.
If you were back in your late teens early 20s what do you wish you had known about working for the FAA? And, if you had it to do over would you become a controller? Not sure what I wish I had known, but I would definitely do it again. For me its like being a pro athlete...you do this awesome job and they actually pay you for it!
What do you like best about the job?
Satisfaction of a job well done. The rush from a busy session.
Your answers will help me provide guidance to help our recent High School graduate decide whether or not to pursue this career.
Visit facilities, talk to people, see if someone will let him spend a few days shadowing them in a facility. Only time will tell.