Woooaaaahhh slow down there! No need to rush! I agree with GalaGirl, there's plenty of time to sort out your questions. Why not just enjoy the NRE for now and practice your communication skills before you dive headfirst into co-habitation? Would you advise your friend that he should move in with a girl he slept with once?
Just because you've known her for a long time doesn't mean you'll be good partners. Take your time with this. Read GalaGirl's links. It seems like you're really getting ahead of yourself.