1 Phone, 1 Music and 1 Pda

I m talking about the Apple’s product, they come out iPhone , a phone that lots of people crazy for it. iPod Touch , a MP3/multimedia player that getting so much attention and now what  ? another PDA is coming and it going to make use of the multi touch technologry ? Is this the reason for not allow adding appointment on iPod Touch ? because that feature will be keep for the iPDA ?

one of my friend ask ” Can’t they just combined ? in stead of break into 3 device ” , but i think the answer is obvious.