What's the official difference between the two?

Trim size, price point, and the fact that it's designed to be thrown away after it's read (although there are other differences like paper quality and typography that come with the package). Basically, the publishers decide, to the point of publishing them under different names, which things they're going to sell to a Wal-mart audience and which are going to get pushed to "serious" bookstores and reviewers.

The majority of genre stuff is originally published in mass-market format, with the biggest sellers having a short run in hardcover first. (Usually six months, as opposed to a year in hardcover for the trade lines).

It used to be impossible for any paperback to get reviewed outside of specialist genre publications. Now, it's sometimes possible for trades, but never, ever for mass.

In the book biz, mass-market strongly correlates with genre, and in the snootier parts of said biz, it's assumed to mean junk.

The majority of genre stuff is originally published in mass-market format

I think I'm a snot too, then. Because the great majority of the SF&F that I read I get in HC, as originally offered.

eta:

the publishers decide, to the point of publishing them under different names, which things they're going to sell to a Wal-mart audience

And I can't remember the last time I saw genre in Walmart that I'd read. Maybe if I were into Stephen King, but it's been a while.

I think I'm a snot too, then. Because the great majority of the SF&F that I read I get in HC, as originally offered.

Nah. It is likely you're going for the stuff that the publishers have tagged as higher-quality stuff within the genre -- and I do the same when I buy SF/F. I really don't see any snobbism there.

But the big difference on the publisher end (and what all those bookselling years make me see being very uncritically voiced in the Salon attitude) is between, say, Knopf and Delacorte. Both are divisions of the same publishing house, but even a hardcover from Delacorte isn't going to get the same attention as one from Knopf. The sales reps won't treat it the same way (in some regions, they won't even be repped by the same person - and the Delacorte sales call will be combined with impulse items to be sold at the cash register), the New York Times will put the top title on the list in the once-a-year twenty-books-on-a-page genre wrapup while ignoring the rest of the catalog, they'll be sold prepackaged by the case quantity rather than in individual units, and much of the time the paperbacks will be stripped of their covers before they even reach the sales floor because the space is worth more at that price point. (The publishers still count the sales, so they don't care).

Readers sometimes resist the term "mass-market", and understandably so, but for the publishers, that's exactly what it is. And the attitude comes down to a lot of people involved in selling the stuff, whether it's sales reps or booksellers or reviewers.

It is likely you're going for the stuff that the publishers have tagged as higher-quality stuff within the genre

Then I'm confused. Because it sounds like I'm making the same distinction the writer is. Not that I knew the terms, but statistically, it turns out I've not considered the mass-market stuff worth my time.

Um, since the average mm paperback retails for about seven bucks these days, they're not getting thrown away so easily.

Trades run in the $11 to $14 range, more often.

edit: and SHIT, I forgot why I wandered in. Very bad news, albeit expected: RIP, Spaulding Grey. They've pulled his body from the East River.

GoddamnitalltofuckingHELL.

Um, since the average mm paperback retails for about seven bucks these days, they're not getting thrown away so easily.

I never said that readers toss 'em, or that readers feel any less about them, or treat as throwaways. But do publishers design and sell them that way? Two words. Stripped. Covers.

Two words. Stripped. Covers.

Heh. Bantam paid the artist $30,000 for the incredibly complicated, multi-colour, cover-within-cover nightmare that was the (gag retch vomit) cover of "Fire Queen". They paid the artist, in fact, as much as they paid me.

It's a horrible cover, and ridiculously expensive, back when mass markets retailed for $4.95.

And suddenly "There's a Bimbo on the cover of my book" (filk by Maya Kaathryn Bonhoff) is going through my head....

The majority of genre stuff is originally published in mass-market format, with the biggest sellers having a short run in hardcover first. (Usually six months, as opposed to a year in hardcover for the trade lines).

This hasn't been true for any genre except romance and possibly horror since at least the mid-nineties, when SF and mystery publishers started shifting more and more books to an initial hardcover printing for library copies and review boosts. There has been a shift back towards paperbacks for initial printings as the industry tries to deal with changing markets, but it's been trade paperbacks in general. The Philip K. Dick Award is an SF award given out to best SF novel published as a paperback original (named because a lot of Dick's work was originally published so), and there was a lot of grumbling for several years because there simply wasn't a lot of SF/F being published as paperback original outside media tie-ins (and even some media tie-ins were published in hardcover).

And the $3 tag is ridiculous. Even children's, YA, and Regency romances (usually shorter and cheaper) are going for $4.99 ea. now; most adult mass market paperbacks are $6.99-7.99.

one of those $3 mass-market sci-fi/fantasy paperbacks.

Dude, where are they selling those? 'Cause I want some. I can't remember the last time I paid less than $7 for a mass-market paperback.

If I spoke to the reviewer face to face, he might be able to convince me otherwise, but I do get a distinct "It's like sci-fi, except it doesn't suck!" vibe from that sentence.