What do you mean by 'compatible' with the GoPro 3? Mounting compatibility (i.e., possible to attach the GoPro to the Goggle in a special way) or that the GoPro can stream directly to the Recon display? Or something else?
By compatible I mean that you would be able to see the live stream just like you would be able to with the Contour+ or Contour GPS. Apparently, because the Airwave uses bluetooth technology and the new GoPro Hero 3 has built in bluetooth it should work? That said, I am pretty sure you can buy a wifi bacpac for an older model of the GoPro that gives it bluetooth functionality so I may go into the store today and test it out.
Either way, you can get a live stream so you can know what you are filming-but with the Contour products.
Below is a link to an article from CNET claiming functionality with the GoPro.