Bitcoin integration is more complicated than most payment gateways. Cyber currencies are very different in their handling than your every day MasterCard or Visa transaction. So it isn't surprising that it hasn't happened yet, without a client backing the project financially.
So, at the request of a few clients, and after discussing this with Nicolas and Jerome at Joomla World Conference this weekend, I'm posting a crowdfunding page for Bitcoin payment plugin development for HikaShop. Anyone who is interested in helping make a Bitcoin payment plugin a reality for HikaShop is encouraged to contribute.
Once the goal is reached, development will begin as quickly as possible and all contributors will receive a copy of the final extension. If the goal is not reached by December 31st, all money will be returned via PayPal to donors, so there's no risk. You'll either get a working Joomla 3.x HikaShop Bitcoin payment plugin or your money back. We will be using the Bitpay method.
This is our first time trying out a crowdfunding approach for custom development, so we'll see how it goes.
You can learn more and if interested contribute via PayPal here:
polishedgeek.com/bitcoin-payment-plugin-hikashop-crowdfunding