On the phone, well, yes and no. You can call people but it's really expensive, something like $1.25 USD per minute. I only use the calling for emergencies or for something quick like if I'm trying to meet someone and we don't see each-other. Internet use is unlimited though. SMS is a little different in Japan, people don't really use it because you can only SMS with people on the same network. Everyone uses email instead.
Ahh, now that is great information. We all can chat online like say MSN or ebuddy for that matter. Unlimited net is awesome~. $1.25 USD per minute is too expensive, yup so we should leave it for desperate times.