Near the end of 2nd year you will be asked to rank your preference for the rotation order. Once you get that via random lottery, you rank all of your location preferences from 1 through 27 (no family med in Florida) and it goes to lottery again. Your options are: Vermont, Danbury CT, West Palm Beach FL, and Bangor ME. Some outpatient sites can fall at other cities/towns in VT or ME. If you are away, you will be housed by the school and you don't have to pay rent. At FL they provide 3 vehicles for the med students to use and they purchase your plane tickets.
You are guaranteed to have everything in VT if you have a WIFE or CHILDREN in the area (or a reason along those lines, girlfriend/fiancee/mydaddy&mommy = no). Otherwise you are welcomed to rank all your top choices in VT but you have no guarantee of getting them. People who did this usually got 4-5/ 7, I got 6/7.
How good a given rotation is at a given location is well-established by now. We have a whole WIKI about it on the med student COMET website. Either way, you can make informed decisions based on the feedback at the site, your weather/location preference, and of course the upper classmen who are very willing to help.
I hope this was coherent.
Edit: I am a 4th year now and I got everything in VT just fine. A few select people ended up having to do one required acting internship in CT, but it's only for 1 month and they will be housed.