I don't really know what his power levels are in this movie. I'd hope it would be a really BIG explosion if it did "knock" him out briefly, but I don't like the idea of an explosion knocking Superman off his feet for even a few minutes. Not even too wild about Zod punching him in the stomach making him cough up blood but they had both be super freaking strong in order for that to happen. I don't want to see a Superman Iron Man or Thor could beat up.
The only way I can wrap my mind round him getting a little floored from the explosion is if he hasn't used his powers in years or something....he's got himself trained to like react a certain way and his brain conditioned. His powers are like muscles that haven't been used in a while. Maybe something like that.
A lot of the other things the guy said are consistent with the other descriptions we've heard so far. I absolutely hate that Jor El might be alive...I don't know why he would be or how. But I'm just going to assume he's a hologram until it's spelled out. I mean why would they show footage of him talking to Clark at Comic Con, where the die hard audience is at, and reveal a massive spoiler like that? CC fans would have been pissed, and Snyder is smart enough to know this. The first picture they revealed of the new suit was evidence of that.