Publication by press release?

Remember my post about the fossil evidence of the whalebone worm Osedax and the mysteriously missing PNAS paper? The paper was finally released by PNAS a week later. When I checked some blog reactions, I found that "press release before publication" is common practice at PNAS. I'm actually kind of flabbergasted.

John Logsdon complained about it two years ago, and three years ago it was Larry Moran complaining. Logsdon condemned the practice as "publication by press release." How are scientists supposed to evaluate claims from a press release? How can the public know that the press release is legit? How can we condemn sensationalistic and bogus "science" press releases that lack formal publication when scientific journals allow results to be announced before they are published? After all, I think we know who likes to publish by press release.

The delays are just a few days, though. Maybe I'm being too hard on PNAS, but I don't think so. (Don't even get me started on the scientific press.) I think the prominent journals have a greater responsibility to set an example of publication excellence. Lots of scientists object to this practice of hyping papers that don't even exist yet, and they should. PNAS should get its act together and start setting realistic press embargo dates.