"So, windknown has contacted me, about a half hour ago, via e-mail. He has told me one of the issues that is keeping Substrate from working on the device, which will probably require me to build a little binary patch for dyld as part of the Substrate installation sequence. This was the worst possible day for me, as I'm traveling back to Santa Barbara today (I'm currently in Texas, having come here to give a talk at The Big Android BBQ), which means this will take me a little longer than I'd like, but clearly getting Cydia and Substrate working on iOS 8 is my highest priority. I thankfully think that I actually can start working a little on one of the Substrate issues using an iOS 7 "model" based on the information provided by windknown, which means I'll lose less time to not having all of my devices with me. (I currently have no clue why Cydia itself is not functioning, but will find out later today when I can see it myself.)" shouldn't be long.