Family Talk Plan Question

[stonefree97]

Ok here's the story. I'm eligible for an upgrade for a new phone and plan on buying a 16gb black iPhone 3G for $299.

I'm currently on AT&T's Family Talk Plan with my Brother (main line), mom, and me. We utilize a plan with 850 Anytime Minutes, 5000 Night/Weekend Minutes, and Unlimited Mobile to Mobile for $59.99 a month plus $9.99 for my phone and my mom's phone.

I DO NOT WANT THE IPHONE ON AN INDIVIDUAL PLAN because it will cost way too much.

After looking at the Family Talk Plan for the iPhone (iPhone 3G, Exclusively from AT&T and Apple - | Wireless from AT&T, formerly Cingular), I realized it was way different..and way more....from my current plan.

--Basically, I was wondering if I upgraded to an iPhone, would we have to change our current Family Talk Plan to the iPhone's plan ($59.99 to $129.99 a month)?
--Or is this plan JUST for iPhone's?
--Also, for the Family Talk Plan listed on that website I posted, does the iPhone have to be the main line OR can my brother remain as the main line in the plan even though he utilizes a different phone?


Thanks!