I'm a current Temple Law student. STAY W/ XP!!!!!!! A friend had to buy a laptop in the middle of the Spring semester and Vista was incompatible w/ large portions of the schools wireless network AND examsoft. I'm pretty sure that Dell (maybe others) still offers to build machines w/ XP if you ask.
wooshi> use Bootcamp to boot into windows when you have to take the exam. Macs will work just fine for everything else.