The main feature I believe we need is the ability for regular users to make payments using their ordinary money and have the gateway automatically do the conversion to bitcoins, thus increasing demand on the currency while allowing merchants to sell for bitcoins.
Bitcoincard also seems like an interesting notion, although it seems to be a bit early for it to be practical.
In your view, do you believe that the way to mainstream is through portals/gateways of this sort expanding further?