How do the teams program there FLL bots?
Drag and drop. Think a version of EasyC designed for LEGOs (whose motors have built-in rotation sensors). I think there is also a “teaching” programming mode where you guide the robot through, it records, and then you fine-tune it. Oh, and you can put loops and such in. (This description applies to NXT and RoboLab. only, and the last sentence or so might not apply to RoboLab.)
what are NXT and RoboLab
NXT is the new Lego processor. There’s a thread discussing it here. RoboLab is a LabView based (I think) programming base for the RCX (the old Lego processor). The third Lego language is the standard RCX language, but I think it only works with the RCX.
The NXT(latest Lego controller)programming language is produced by NI. You can use an internet based demohere.
It is an extremely simple drag/drop interface that anyone can learn. I mentored two FLL team last season, and they were able to learn enough to make their robots work.
The best way to learn is buy a kit, and play.
If you spend a few hours going through the guided tutorials you will look like a master to most people.
Yeah, and if LEGO Mindstorms NXT programming isn’t hard enough for you or you feel too restricted, you can download the LEGO Mindstorms NXT Toolkit for LabVIEW 8.2 (yes, the same LabVIEW 8.2 you got in FRC this year). The LabVIEW toolkit allows you to use the full power of LabVIEW to program the NXT brick, create your own custom blocks you can use within the LEGO Mindstorms NXT environment, control custom sensors, and more!
LabVIEW has just invited you to expand your mind. RSVP now! 
-Danny