The folks over at iF Magazine posted an excellent interview with him that you can get a taste of below:
iF:When did the OMEN remake come back into your life?
SELTZER: It really didn't. I was not consulted. In fact I was kept out of it. They had hired another writer and he didnít contribute nearly enough to get a screenplay credit. He did a few things, but it was only on 11 pages out of 121 and the Writerís Guild, you canít get a credit if thatís the case. So after arbitration, my name was put on it. It was still my script. Scene for scene. Character for character, line for line, even the punctuation was the same on the page. So they really couldnít say it was another writerís work. I was never involved with it at all. When I saw the picture with my name on it, I realized another director had turned it into a whole other ballgame and I saw it sitting next to Dick Donner.
It made us appreciative of the fact that we were allowed to make a movie [back in 1978] that was not in any way patronizing to an audience. We didnít spell out the story, we let the sense of discovery go on scene by scene by scene. It was a different vision. Iím not saying that the new film is a bad movie, it was a very different movie, and it was not the movie I would have imagined being made out of the OMEN. Every phase of the original, from the shooting to the production design, to the directing, it all adds up. There has to be a singular vision from [a director] like Donner.
Seltzer gets into a lot of interesting subjects in the interview, including why he didn't write the sequels, where he thought they went wrong, and just what it's like to try and follow your heart rather than your pocketbook in the Big H.
Now go read the whole damned thing! You'll be glad you did.