They discovered some issue in testing. They are trying to work it out. He's got a lot of time and money into this already, so I'm 100% positive he wants these out and on the market even more than we do, and his frustration with that not being the case is higher than ours.
At this point, it's no longer just right around the corner. He doesn't know when. We don't know when. And even if he had an estimate, I suspect he'd be reluctant to provide that estimate and risk missing the release date again. I doubt we'll hear about this again before it has passed all of his standards and testing and is ready to ship.