volt the way i see it is that mms sms and video calling ,gsm calling are one way of doing something

email IM(with video call option) skype is another way.

at the mo if you can video call - you pay as part of your phone bill.(a certain amount per minute) like when you pay for mms- you pay per mms

if you im video you pay by data, when you email a pic, or postr one on a pic site or on a social network site you pay by data .most people in my country with phones like these have the web bolt on(you cant get a contract iphone without unlimited data)

the switch is between gsm to data, not mms to video calling.