The Earth-1 subplot may not have been great, but at least it paid off with this (admittedly massively telegraphed) climax. With everyone safely back on Earth-1, Jay closes the final breach, and then stands with his back to it, celebrating like a NFL player who's just scored a touchdown. And then, of course, Zoom reaches through the breach, puts his arm through his chest, and drags him back to Earth-2, quite possibly dead. Maybe it wasn't the most shocking result, but it worked nonetheless. However, the question remains over whether Jay is actually dead. After all, he hasn't really had a lot to do this season, and the past episodes are the ones where he's finally been the Flash, so it would be something of a waste to get rid now (not that I'd have any major complaints, but still). We don't actually see him die, so it's very much up in the air, and in honesty his being dead would be something of a surprise, with another option more likely.