HOW DOES THE IPHONE PICTURE MESSAGING WORK?

I assimilate which you have to make use of email to send cinema with the iphone but lets contend which i wish to send a design to my partner who has a blackberry pearl but an interent plan. Will she be means to get the design and download it only regulating media net? And would she be means to send me one but carrying the internet plan? She has the brand new pearl but does not have the interent devise for it but does have media net capabilities.