Well as you already know I'm a USMMA grad and current Navy physician so I'll try to answer as best I can. Obviously I could write pages and pages, but I'll try to keep it a bit shorter
First of all, where do I start? Would an Academy be the right choice? What about ROTC? Or does the undergrad school really matter?
School matters to the point that if you take two people with the same GPA but one's from Harvard and one is from no name state school the one from Harvard has a slightly better chance. The most important part is to simply do well wherever you go. I know plenty of people from 'unknown state school' who are physicians, they simply did well, did extracurriculars, and did well on entrance exams. It's really not that huge of a deal.
The question as to service academy/rotc is a bit more difficult. If you get in to a SA/ROTC and do well it will be a plus on your medical school application. The only issue is that the number of people allowed to select medical is limited each year. With that being said I've never heard of someone who wanted to go medical and was good enough to get into medical school not being one of the people who was in the position to be selected for the medical corps.
I've heard (but I am not sure how accurate this is) that if you go ROTC and they don't select you for medical school, you don't get in. Hmmm...
True. "Needs of the Service" drive how many are allowed to go to medical school; however, if you are a strong applicant for medical school you will be a strong applicant for one of those slots.
Second, after undergrad, what happens? Say I go to a civilian college and then go to medical school; would I enlist and let them know that I am in medical school? I know KP2001 went to an Academy and then went to USUHS. How does that work?
If you go to a civilian college and are applying for medical school you simply apply for the medical school scholarship (HPSP) at the same time. For the past several years if you were accepted to medical school you would qualify for the scholarship. They are hurting for numbers; however, this gap is closing now. If accepted for the scholarship you will be commissioned into the Reserves for your time in medical school. (There is also USUHS, where you are on active duty....the application process is nearly identical to civilian schools)
If you go to a service academy it's basically the same deal, except you also need to apply for medical corps during service selection (not available at USCGA, and not necessary at USMMA)
Am I correct in saying that the service pays for medical school?
If accepted for the scholarship the school is paid for and you are given a monthly stipend. If you attend USUHS you get paid as an active duty officer.
Third, after medical school, what happens?
Unfortunately when you graduate medical school you are in for at least 3-7 more years of medical training. During fourth year of medical school you will apply for your residency of choice (Family Practice, Surgery, Psychiatry, etc etc). This is called "the match" and for some specialties (ophthalmology, orthopedics, dermatology, radiology, etc) is highly, highly competitive. Residency is the time you hear about incredible working hours: the current limits are 80hrs a week, 30hrs in a "day", and one day off in seven. For the most part expect to be in the hospital around 100hrs a week with about two weeks of vacation a year until residency is over. The 30hr days (come in at around 0600 and leave at noon the next day)will be approximately every 3 to 4 nights for the great majority of that time.
A large percentage of military doctors will do one year of training after medical school and then be sent out to the fleet to be "General Medical Officers (GMO's)" where you are basically the primary care doctor for the soldiers/sailors/airmen/marines. You are assigned to an operational unit and deploy with them. After 1-3 years of that you will return back to the residency you were accepted in.
What is the whole military doctor career like?
Fairly similar to that of a civilian physician, except for the whole deployment thing. You will get some opportunities that civilians never get (fly in jets, land on carriers, go to Haiti on a hospital ship, etc) and they will get opportunities you never get (work for Operation Smile, Doctors without borders, etc).
Career progression is usually: 4yrs medical school, 1yr residency, 2-3yrs GMO, 2-6yrs residency, 3yr post-residency utilization tour (usually overseas/shipboard/less desirable US locations), then Medical Center staff physician (can vary between small hospitals to positions at the major medical centers). You can move anywhere between every 2-3 years to where I've seen people at the same hospital for over 10 years. For the most part once you are beyond your 'post-residency tour' you will be assigned to a hospital and additional duty to some sort of operational platform/field hospital. You will also be randomly assigned to fill billets on 6mos-1yr deployments a few times throughout your career.
How is the pay/time commitment?
Pay for most specialties is around 1/3rd of what a civilian of similar specialty and years would make. A military physician will max out in pay in the low $100,000 region give or take.
Time commitment is four years for HPSP and seven years for USUHS. This is in addition to any undergrad commitment you may have. This time is not paid back during any residency time so truly the minimum commitment is more like 5yrs for HPSP and 10yrs for USUHS.
Do you have any regrets about choosing this path?
None, yet. I'm currently a GMO/flight surgeon and enjoy my job. I get to support the troops on the ground and when deployed feel like I'm really giving something back. I also seem to find a great sense of pride in those physicians who are working at the hospitals that are getting the majority of the OIF/OEF injuries. It is an absolute honor to take care of the wounded. They impress me on a daily basis.
There are obviously trade-offs in becoming a military physician. The most glaring is pay. Many in mil-med have a huge issue with using people with one year of training to take care of our active duty population, some also feel this delay in training is a big negative. Some also feel that the current patient population does not allow them to keep their skills as sharp as someone in the civilian world. In particular ER docs don't see enough true emergencies when in the US if they only work in a military hospital so most will moonlight at civilian ER's to keep their skills sharp.
Overall it is a choice that one needs to go into with a lot of information. Be wary of most recruiters trying to tell you information about the medical corps as most have no clue even if they are the medical corps recruiter.
Your goal right now should be to get into the college of your choosing and do well there. Choose a major that you like, not necessarily the one you think will get you to medical school. (you don't need to be a science major, that's a huge myth, you simply need the pre-requisite courses). Some people will try to steer you clear of service academies; however, if you feel that is the best school for you it is a valid path to medical school.
Okay, I've written too much