The Retron 5 did indeed release, but from the sounds of it, Hyperkin didn't release nearly enough to meet preorders. I preordered through a local store and I'm still awaiting fulfillment on the gray console. The black console won't be released until September, maybe..but that was only announced within the last few weeks, I think. Maybe around the time they raised the price by $40?
It can kinda be considered vapourware, though, maybe, because I think the Retron 4 that was never released just sort of morphed into the Retron 5 after that one was delayed for nearly a year, too.
Well, you definitely gotta get it now. (My only fear with the Cave is the $17 price; I don't think I'm going to get the replay value that I do from a $5 iPad game. The demo would be a no-brainer, though, so test it out and see for yourself.)