I read the introductory part explaining rails and PostgreSQL and that was real good. Yes, it's written by a PostgreSQL developer - which is both a blessing and a curse. It means it is technically correct and thought out and complete; it is also written from a particular point of view. But I doubt you have a problem with that, do you?
Then the interview part - yes, the answers are VERY marketingy. The dude who answered the questions either is a marketeer, had marketing experience or was helped by a marketing person. And obviously didn't realize that is absolutely the wrong tone for LWN.
But you can edit what someone answers to your questions only so much - and I wouldn't blame LWN for publishing it like this. All in all - for me, knowing not too much about Rails and database stuff, it was a good read. Next time, tell the interviewee that this is for LWN - not a marketing site and it'll be perfect.