Browsing the internets this morning I came across this exciting piece of news...it appears people ARE working on the smart strap development that has been rumoured sine the advent of the Pebble Time and Time Steel/Round. 

http://www.prweb.com/releases/FitPay/Pagare/prweb13078408.htm

A summary below: 

Fit Pay, Inc. and ConnecteDevice announced today that they have developed a smartstrap for the Pebble Time family of smartwatches. The new smartstrap, called Pagaré (TM), enables Pebble Time users to transact secure, contactless payments at millions of retail locations.