Dual chip phone for payments without option to talk

Over 10 years ago my former employee (bank) with mobile manufacturer was dreaming of building dual chip mobile handset. It was planned to have one chip card for SIM and other for card payments. It never realized. Since that I have been following several mobile payment trials. Now I am keen to hear how Google will solve this dilemma.

When browsing thru really old presentations I have given out on this topic yesterday night, I started to think again this idea. It was brilliant but timing for technology wise was lacking. 

Since that, I have questioned why we should have payment option to mobile phone. Is that the device we like to use when paying small errands? Could that device/ card be something else. Few years ago no-one was talking iPad or any other device. At the time we have first really used mobile solutions, question is how many will use mobile phone for that. Could it be key chain containing sim card for internet access and other chip for payments with small screen. Or could it be plastic card like today, but other end a bit broader with small screen and access to internet. This could be use as credit card like today, but same time for browsing like iPod. It could be possible, if Apple makes iPods thin enough.

Idea would be having basic open platform operating system like Meego or Android where card/ key chain/ some other payment device would operate. There would be standardized card payment and online banking solutions, but all the other extra services would be be really open for innovators. 

Most interesting thing, why I would like to talk with my payment card. For that reason I have phone. 

Question is, what will be next payment platform replacing first cash and then plastic.